Page 1

A sonoran Oasis Developing a Local Food System for Ajo, Arizona

Deep in the Sonoran Desert, the community of Ajo, Arizona, is facing health and economic challenges. Ajo is dependent on the continued availability of imported foods, leaving people vulnerable to conditions over which they have little power. Productive and ecologically sound land use is achievable through modern adaptations of traditional Sonoran Desert farming and water management techniques that maximize food production while respecting the limits of the desert.

The Conway School of Landscape Design is the only institution of its kind in North America. Its focus is sustainable landscape planning and design. Each year, through its accredited, ten-month graduate program just eighteen to nineteen students from diverse backgrounds are immersed in a range of applied landscape studies.

Ahron Lerman | Susannah Spock | Sean Walsh

Conway School of Landscape Design Winter 2011

Contents Executive Summary


Introduction 2 Food Security in the Desert


Land requirements


Water in the Desert


Soil & Vegetation


Land Availability


Vision: Ajoasis


Works Cited


Appendix A


Appendix B


Appendix C


Appendix D


Appendix E


Appendix F


Appendix G



“The [tepary] bean, isn’t just a bean. When you look at the legends, the stories, the traditions—it’s more.” -Terrol Dew Johnson, Tohono O’odham Community Action Co-Director

Acknowledgments We would like to thank the International Sonoran Desert Alliance for sponsoring this assessment on behalf of the Ajo Regional Food Partnership. The energy of the partnership and its supporters were vital to the production of this document. Thank you to the people of Ajo for their hospitality during our visit, and for the time they took to share their thoughts and experiences. Thank you to the Tohono O’odham and Hia C-ed O’odham people who shared their traditions, culture, and knowledge with us. We have much gratitude for the Conway School of Landscape Design staff, faculty, alumni, and classmates for their patience, insight, guidance, and support.

© 2011 by the Conway School of Landscape Design, 332 South Deerfield Road, Conway, MA 01341. All rights reserved.


Executive Summary A Vision of Local Food Production for Ajo, Arizona Deep in the Sonoran Desert, the community of Ajo, Arizona, is facing health and economic challenges. High rates of obesity and diabetes are compounded by a lack of job opportunities and a struggling economy. Ajo is dependent on the continued availability of imported foods controlled by distant markets and requiring fossil fuels for production and transportation. This system leaves people vulnerable to conditions over which they have little power.

limiting factor in desert agriculture, water supplies have heavy demands and face dwindling reserves. The potential for reuse of Ajo’s wastewater represents a tremendous opportunity to produce food and create habitat without further depletion of the aquifer. Though space available for food production in Ajo is limited, public rights-of-way, backyards, and vacant lots could provide space for increased food production in town, while larger scale cultivation could potentially occur on parcels nearby.

The Tohono O’odham and Hia C-ed O’odham have lived in the Sonoran Desert for thousands of years. A traditional food system adapted to single-digit rainfall totals and triple-digit heat provided the O’odham people with a nutritious diet that included mesquite flour, beans, melons, squashes, corn, and greens. In Ajo, local gardens provide some fruits and vegetables, though fresh food is not always available. Recently, the town has seen the emergence of a local food system through a farmer’s market, community gardens, pomegranate orchard, and more.

In a healthy ecosystem, waste becomes the basis for good soils, water is continually recycled, and diversity creates resilience. Largeand small-scale composting would return nutrients to the earth, fortifying the desert’s poor quality soil. Water conservation and reuse would maximize a limited resource, while cultivation of desert-adapted crops would create more resilient food production better able to handle the desert’s natural stresses.

To be sustainable, a food system needs to be appropriate for the place. Modern agricultural practices in southern Arizona have disrupted desert hydrology, and continued shortages of water are expected. As the most significant

In this vision, the unique flora and fauna of the Sonoran Desert coexist with a productive landscape, creating an oasis in harmony with ecological and hydrological processes: Ajo oasis or AjOasis. This vision is achieved through modern adaptations of traditional Sonoran Desert farming and water management techniques that respect the limits of the desert.

A Sonoran Oasis Executive Summary


Introduction Ajo’s Health and Economic Challenges Air conditioning and deep wells have helped Ajo residents adjust to the extremes of the Sonoran Desert. But these modern innovations have not helped Ajo overcome other serious challenges. The 2000 Census showed that 23 percent of Ajo lives under the Federal Poverty Level. The median household income in 2000 was just $25,618 (compared to a U.S. median of $41,994). Since the local mine closure, fully half of the working age adults in town are jobless. According to a grant application written by the International Sonoran Desert Alliance, a lack of employment opportunities causes many young people to leave town.

Food Security Might Help Alleviate Some of these Woes By providing more fresh food choices and connecting people more directly to the sources of their food, a food-secure system for Ajo might help reverse these trends and revive Ajo’s struggling economy.

Ajo Celebrates Food

Food security has been defined as “a condition in which all community residents obtain a safe, culturally acceptable, nutritionally adequate diet through a sustainable food system that maximizes community self-reliance, social justice and democratic decision-making” (Hamm and Bellows 2002). Ajo, Arizona

Health issues are affecting Ajo residents of all ages. According to Desert Senita Health Center, in the 2009-2010 school year Ajo Unified School District had at least a 32 percent obesity rate in every grade; sixth grade represented the highest rate at 57 percent. Ten percent of Ajo is affected by Type II diabetes, while Ajo’s nearest neighbors, the Tohono O’odham Nation, have the highest rate of Type II diabetes in the world at over 50 percent (TOCA 2009). These rates have led the Pima County Health Status Report Card to conclude that 57 percent of deaths in Ajo are premature.

Food security means people have access to healthy and uncontaminated foods that will not make them sick. In a food-secure system people have access to foods that reflect their cultural, regional, or religious backgrounds. A foodsecure system feeds everyone, including the poor, elderly, and disabled. A food-secure system doesn’t produce food at the expense of the health and vitality of the environment or create social inequalities, nor does it rely on imported or nonrenewable resources to fuel its major components; a food-secure system’s wastes become its inputs. In a food-secure system people have choice. How might Ajo become more food secure?


A Sonoran Oasis Introduction

The Ajo Regional Food Partnership Battles Obesity and Diabetes Recognizing the possibilities of a more foodsecure Ajo, a number of organizations have sprung up in the last few years, igniting a new energy around local food.

The Ajo Regional Food Partnership (ARFP) is a collaborative effort between eleven organizations based in Ajo and the surrounding region: • International Sonoran Desert Alliance (ISDA) • Desert Senita Community Health Center (DSCHC) • Ajo Unified School District • Ajo Community Garden Consortium • Ajo Community Supported Agriculture (CSA) • Hia C-ed O’Odham Alliance • Pima County Health Department • University of Arizona-Pima County Cooperative Extension • Ajo Botanical Company • Tohono O’odham Cultural Center & Museum • Pima County Natural Resources, Parks & Recreation

The goal of the Ajo Regional Food Partnership is to transform the current food system into one in which “food would be grown, distributed, and processed locally with robust educational support not only for the growers, distributors, and processors, but also for the whole community. The result, we believe, will be improved community health and an enhanced local economy.” One member of the partnership, the Ajo Community Garden Consortium, has been encouraging backyard gardening and has formed a community garden that uses captured rainwater from the roof of the Curley School. The garden grew from five plots its first year to twenty-eight its second, with plots for area homeschooled children and the GED course students. In the winter of 2011, the Community Garden Consortium broke ground on a second community garden on a lot owned by the Ajo First Assembly Church. The Ajo CSA group makes weekly deliveries of organic food from Crooked Sky Farm in Glendale, Arizona. The CSA organizers also operate a small weekly farm stand, selling produce from Crooked Sky Farm and the community garden. ISDA has started a small pomegranate orchard, launched a culinary micro-enterprise program called Ajo Cooks! that encourages local culinaryfocused entrepreneurship, and runs a variety of educational programs on food preparation and making healthy food choices. Desert Senita Community Health Center (DSCHC) and the Pima County Health Department are focusing intensively on educational approaches to combat diabetes and obesity. DSCHC also houses the Ajo WIC program, a federally-funded initiative to provide low-income women and young children with

A Sonoran Oasis Introduction


nutritious foods and education. A small garden provides WIC families with the opportunity to learn about growing their own food. Behind DSCHC’s dental office, a staff garden encourages health center employees to grow some of their own food. According to the WIC Director, the center’s behavioral health department is also planning an aromatherapy garden, which will include herbs and edible flowers and a garden labyrinth. The Ajo Unified School District has added a culinary arts elective, and partnered with the county health department to start student gardens. The health department has also partnered with DSCHC to document the obesity rates of students.

ARFP has recognized fifteen other Ajo-based and regional groups as supporters: • • • • • • • • • •

• • • • •

Ajo Community Food Bank Ajo District Chamber of Commerce Ajo Garden Club Ajo Public Library Ajo Women, Infants, and Children (WIC) Program Healthy O’odham Promotion Project Key Ingredients Oasis Cafe Olsen’s IGA Policy Team, CDC Project: Communities Putting Prevention to Work San Xavier Cooperative Farm Tohono O’odham Community Action (TOCA) Tohono O’odham Community College (TOCC) Tucson Community Food Bank University of Arizona Rural Health Office

The Ajo Community Food Bank mostly distributes canned and packaged goods, but donations of fresh produce are always in high demand.


A Sonoran Oasis Introduction

Ajo Community Garden Consortium’s garden behind the Curley School grew exponentially between its first and second years.

A Sonoran Oasis Introduction


Food production is difficult in The Intense Sonoran Desert Climate The Tohono O’odham have called the Sonoran Desert home for thousands of years. With single-digit rainfall totals and triple-digit heat, surviving in the harsh environment of southcentral Arizona isn’t easy. By adapting to the heat and the rhythm of the rains, the O’odham established themselves along the Salt, Gila, and Santa Cruz Rivers. Their intimate knowledge of weather patterns dictated the establishment of planting and harvesting cycles.


Food Security in the Desert

Rainfall average per month

Ajo experiences an average of 155 days per year when temperatures surpass ninety degrees, contributing to an average yearly high of eightyfour degrees. Temperatures over 100 degrees are typical May through September.

Phoenix Ajo


Pacific Ocean

Ajo’s Economy Has Historically been Based on Mining Mexico

Sonoran Desert Ajo sits in the midst of the Sonoran Desert.

According to the Western Regional Climate Center, Ajo receives an average of just 8.35 inches of rain per year, which is not evenly dispersed throughout the year. For example, the month of June averages just sevenhundredths of an inch of rain, and only July and August receive an average of more than one inch.


A Sonoran Oasis Food Security in the Desert

For centuries, the O’odham people mined Ajo for hematite, a hard oxide mineral with a high iron content and reddish color. In 1854, Peter Brady came to Ajo and started the Arizona Mining and Trading Company, the first mining company in the state of Arizona. For years, production in the area was slow as surface ores became increasingly difficult to find. Large-scale mining didn’t begin until 1911 when former Rough Rider Colonel John Campbell Greenway bought the Ajobased Cornelia Copper Company. New groundwater sources allowed Greenway to develop an innovative leaching method to process the lesser grade ores, which expanded production exponentially. The mining company’s Tucson, Cornelia & Gila Bend Railroad connected Ajo to the global ore market (Pima County 2001).

Ajo’s New Cornelia Mine Pit lies just to the south of town. Photo Credit: USGS

By the 1950s, the mine, now owned by Phelps Dodge, was the largest producer of metallic ores in the country (Pima County Staff 2001). With the mine employing thousands, the town’s population peaked in the 1960 census at 7,049. However, a bitter strike in 1985 forced the closure of the mine and its rail line. Ajo’s population subsequently plummeted from a 1980 total of 5,189 to just 2,919 in 1990—a loss of over 43 percent in the decade. According to the 2010 census, Ajo’s population has rebounded to 3,304, possibly due to the influx of personnel working at a new Border Patrol station nearby.

Until mining ceased in 1985, Ajo was a company town where Phelps Dodge provided most food and services for residents, including housing and supermarkets. Following the mine closure the company divested many of these assets and many businesses closed. Ajo has had no major industry or source of employment since that time. Ajo’s dependence on exporting minerals to the fluctuating global market left it economically vulnerable, as the closing of the mine has shown. Members of the Ajo Regional Food Partnership believe that relying on imported food also makes Ajo vulnerable.

Freeport-McMoRan bought Phelps Dodge in 2007, but their plans to reopen the Ajo operation were put on hold after the economic collapse in 2008. It is estimated that 135 million pounds of copper and 25,000 ounces of gold could still be extracted annually and many residents continue to follow the market price of copper as a predictor of the future of the mine (Pima County 2001).

A sonoran Oasis Food Security in the Desert


A Global Food System leads to Local Food inSecurity Like most of the country, Ajo relies on a global food system. The term “food system” refers to all the “food chain events” from growing to processing to distributing (Winne 2004). A global food system sources food from all over the world. It is not uncommon to find New Zealand apples, Chinese shrimp, and Peruvian grapes alongside American grains in the average American grocery store. By air, boat, rail, or tractor-trailer, these foods converge at major distribution centers to be sold throughout the country. While these systems supply Americans with inexpensive foods in any season, there are hidden health, social, and environmental costs. Production The predominant way of growing food in America is on large-scale industrial farms, owned by a few large corporations. Currently, just four companies control 84 percent of the U.S cereal market and it is estimated that just two companies, Cargill and Archer Daniels Midland, purchase one-third of all the corn grown in the U.S. and own its entire line of production, from farm to table (Pothukuchi et al 2002; Pollan 2006). The global market’s production cycles are becoming more chaotic due to unpredictable weather extremes that some are associating with climate change. In the summer of 2010, 25 percent of Russia’s wheat stocks literally went up in smoke as record heat and wildfires ravaged the country (Elder 2010). For the thirdlargest wheat exporter in the world, losing a quarter of its crop halted exports and caused concern over global wheat shortages. Accordingly, global wheat prices soared 42 percent in the month of July alone—the largest increase in at least fifty-one years (Associated Press 2010).


A Sonoran Oasis Food security in the Desert

Processing Food quality is frequently compromised at centralized processing plants. Industrial facilities can poison large numbers of people with a single mishap. Contamination at two Iowa egg companies forced the nationwide recall of over half a billion eggs in August 2010, and a 2009 national salmonella outbreak in contaminated peanut butter from a Georgia plant sickened over 700 in forty-three states and is blamed for nine deaths (Suddath 2010; Center for Disease Control 2009). According to National Public Radio a 2010 survey indicated that these and other instances have left 61 percent of our country worried about food safety. Distribution A global food system is dependent on fossil fuel resources for everything from production to transportation. As Ben Hewitt writes in The Town That Food Saved (2009), “On average, every calorie that lands on your plate soaked up eleven calories of fossil fuel energy as it was sown, grown, harvested, processed, and shipped. When the price of those eleven fossil fuel calories doubles, then triples, and finally rises exponentially, the cost of that single calorie of nourishment will rise, too”(Hewitt 4). Anything that could disrupt the regular movement of our oil-dependent planes, trains, and tractor trailers—like a natural disaster, terrorist attack, or unrest in oil-producing countries—can expose the system’s weakness. One current vulnerability in Ajo’s food supply is Highway 85, currently the only route used to bring food into town. Even if dwindling oil supplies don’t increase the cost of food, the limits of our industrialized system are exposed in other ways. Due to droughts and increased production of biofuels, 2007 global grain stocks dropped to the lowest levels seen in thirty-four years. By early 2008, rice prices doubled in just a single month. In response, wholesale seller Costco began

Arizona and New Mexico currently import over 97 percent of their food from out of state (Nabhan 2011).

A sonoran Oasis Food Security in the Desert


rationing the amount of rice consumers could purchase. As Hewitt (2009) simply stated, “That’s right: Food rationing, in the United States, in 2008.” A local food system may provide security from global price increases by producing food near the consumers. Consumption In 1820, there were essentially two options for consuming excess corn: turn it into pork (as feed) or alcohol. Today, technological advances can turn excess corn into a variety of engineered food products, “everything from chicken nuggets and Big Macs to emulsifiers and nutraceuticals,” according to Michael Pollan in Omnivore’s Dilemma (2006, 103). Overproduction of corn creates 17.5 billion pounds of high-fructose corn syrup, a relatively unheard of commercial food ingredient in 1980 that has no nutritional value (Pollan 2006). It has been linked by a University of California study to heart disease and diabetes (Rogers 2009).

Produce Available: IGA, Food Bank, CSA Produce Not Available: Convenience and Dollar Stores Produce May be Available: Restaurants Produce can be used as an indicator of the availability of healthy food options. Few outlets in Ajo meet this criterion.


A Sonoran Oasis Food security in the Desert

In 2010, the United Nations’ Food and Agriculture Organization estimated there were 925 million malnourished people in the world, which the current industrial food system has failed to feed. Small-scale, decentralized farms might provide a solution. “We won’t solve hunger and stop climate change with industrial farming on large plantations,” a report released by the UN’s Special Rapporteur on the Right to Food notes. “The solution lies in supporting small-scale farmers’ knowledge and experimentation, and in raising incomes of smallholders so as to contribute to rural development” (De Schutter 2010). The report noted that small-scale ecological farming could double global food production over the next ten years. As a small rural town, Ajo could make a positive impact on its own food security and development by increasing its number of smallscale growers.

Waste Industrial farms consolidate organic waste in large quantities, making it a liability and health hazard, rather than vital nutrients to be cycled back into the system. For example, in 1995 an eight-acre cesspool in North Carolina burst, sending 25 million gallons of hog excrement into the New River, killing an estimated 10-14 million fish immediately (Robbins 2001). A local farm can more easily turn smaller quantities of organic matter into amendments to help build the soil for plants.

Gardens Backyard and community gardens, popular as “victory gardens” during the First and Second World Wars, have received increased attention lately due to the recent economic downturn. First Lady Michelle Obama’s vegetable garden at the White House is its first since Eleanor Roosevelt’s victory garden in the 1940s (New York Times 2009). These gardens, combined with farmer’s markets, Community Supported Agriculture (CSA) shares, and on-farm sales contribute to an alternative network of growing and distributing food locally.

Manure lagoon from a nine-hundred-hog operation Photo Credit: USDA Natural Resources Conservation Service

Local Food System Opportunities In contrast to a global system, a local, decentralized food system can put consumers in direct contact with producers. More numerous and smaller facilities sharing the responsibility of food production and distribution means that a single mishap at one plant does not compromise the safety and continued availability of a staple food item for the entire nation. Proximity between consumer and producer can create important relationships, such that producers are able to respond quickly and effectively to consumer desires and concerns. Face-to-face accountability in a localized food system can ensure higher food quality and cleanliness unseen in a highlyregulated, yet anonymous and vulnerable, centralized food system. As local-food advocate and farmer Joel Salatin says, “You can’t regulate integrity” (Pollan 2006, 235).

Home food production was a national priority when the U.S. Department of Agriculture used this poster to promote victory gardens during WWII. Photo Credit: Wikimedia Commons

A sonoran Oasis Food Security in the Desert


Closing Loops Case Study: Hardwick, Vermont

Imagine sitting down at a restaurant to eat a meal raised by local farmers from regionally grown seeds that were nourished by locally generated compost. The folks at the table to your right might have grown the salad greens on your plate; the table across the room might be filled with farmers who raised the beef in your bun; the beer in your stein might be brewed by some of the patrons at the bar. You’re imagining the town of Hardwick, Vermont.

town supporting itself in this Global Age by conducting business locally. Nearly everything from seed to harvest can happen in and around Hardwick—something hardly any other town can currently boast. Hardwick’s “agrepreneurial” (a word Hewitt uses to describe the region’s agrarian entrepreneurialism) movement is inspirational because its model is transferable and simple to understand.

Nestled into the northern hills of the Green Mountain State sits this former mining town of 3,200 residents, roughly the same population as Ajo. Hardwick’s low profile has been disrupted by the recent media attention it has garnered for its local food economy, which has revived the town and generated nearly 100 new jobs (Hewitt 2009). Ben Hewitt recently profiled Hardwick in The Town That Food Saved to understand how the town has transformed itself and the implications of such a process. Hewitt finds a remarkable closed-loop food system that turns waste into product. He explains, “One of the great strengths of Hardwick’s food system…is the ease and clarity with which it articulates circular agriculture.... They make it incredibly simple to demonstrate roundness in food production: The seeds are sown and grown into vegetables. The vegetables are served, and whatever scraps remain are turned into compost. The compost fertilizes the seed and vegetable crops. And so on” (Hewitt 2009, 51). Hewitt does not describe a town that has found trendy new cash crops, or is relying on space-age greenhouse technology or high-tech growing materials to create a new influx of cash. Hewitt describes a


A Sonoran Oasis Food security in the Desert

Hardwick’s new local food economy is centered around its historic downtown. Photo Credit: Wikimedia Commons

For its size, a surprising number of agrepreneurial businesses call Hardwick home. Some of the companies in town include Vermont Soy Company, High Mowing Organic Seeds, Jasper Hill Cheese, True Yogurt, Claire’s Restaurant and Bar, Pete’s Greens, The Highfields Center for Composting, Honey Garden Apiaries, and Buffalo Mountain Co-op. While sitting in on a monthly meeting between many of the agrepreneurs, Hewitt realizes, “Represented in this single room, on the top floor of an old farmhouse in rural Vermont…was the beginning of something circular: compost, seed and farmer…They represented

something much larger indeed: They represented the slow, hard bending of...our linear agricultural system” (Hewitt 2009, 209). When looking at Ajo’s potential for local food production, one can see some similarities to Hardwick. For one, the towns are remarkably similar in their population size and share a common bond in their histories as former mining towns. Both are home to a number of organizations excited about reviving the local economy around food-based businesses; the Ajo Regional Food Partnership (ARFP) comprises eleven organizations, while at least fifteen others have been identified as additional allies.

The historic Curley School plays a central role in the localization of Ajo’s food system by hosting a farmstand, community garden, pomegranate orchard, commercial kitchen, and food-related events.

Ajo could learn from Hardwick and the efforts there to capture organic material for composting and reuse. In addition to many on-farm composting operations, Hardwick’s Highfields Center for Composting creates compost on a commercial scale, selling it to small farms, larger-scale producers, and home growers. Ajo’s organic materials are currently deposited straight into the landfill,

a potential resource that can help rejuvenate Ajo’s nutrient-poor soils. Despite the dramatic differences in climate between northern Vermont and southern Arizona, both regions share a long agricultural history. Hardwick’s fertile soils have supported small farmers for hundreds of years, while the Tohono O’odham and Hia C-ed O’odham have subsisted on floodplain farming and wild-harvesting in the Sonoran Desert for several thousand years. Both Hardwick and Ajo have access to regionally adapted seeds. Hardwick‘s growers can purchase their organic and heirloom varieties from High Mowing Organic Seeds (who in turn, contracts Vermont farms to grow out their seed stock each year). Similarly, Ajo is just a couple hours from the Tucson-based Native Seed/SEARCH, a seed bank specializing in preserving endangered arid-land-adapted seeds. It’s not hard to imagine a bright future for Ajo when considering what Hardwick has accomplished and the similarities between the two towns. Hardwick has established itself as a town on the forefront of a new food-based economy, bringing jobs and attention to the small town. In fact, Hardwick’s small size has worked in its favor, according to Hewitt. “This is a very human endeavor,” he writes, “ and Hardwick, clearly, functions on a very human scale” (Hewitt 2009, 219). Ajo shares that human scale, and a similar population of hardworking, community-oriented residents who seem poised for a transformation. By closing loops of its own, Ajo could be the next town that food saves.

A sonoran Oasis Food Security in the Desert


A local food system also keeps money circulating within a community, and increases the number of times money exchanges hands before leaving a community, which is known as the “multiplier effect” (Jones 2010). For example, a local food producer has a vehicle fixed at the local car repair shop, whose owner pays the local barber for a haircut, who then purchases food from the grower, thereby increasing the number of individuals benefiting within a community. Under the current predominantly industrial model, most of the money spent on food grown far away never even makes it to local economies; of the average “food dollar,” the farmer receives just 11.6 cents, while the rest stays in the pockets of large processing, marketing, and distributing middlemen (Canning 2011). By producing its food locally, Ajo can begin to retain more of its food dollars for local businesses and residents. Tohono O’odham Food System The Tohono O’odham developed a resilient food system based on varied production strategies. As described in From I’itoi’s Garden, a publication by Tohono O’odham Community Action (TOCA), “Three primary food production strategies provided a rich and varied diet.” Ak-chin farming (see page 20) used the summer monsoons’ flood waters to irrigate thousands of acres of nutritious, desert-adapted plants; wildharvesting provided seasonally abundant foods that could be eaten fresh or preserved; and hunting desert animals, like rabbit, deer, and javelina supplied important protein supplements. The Tohono O’odham also traded regionally with neighbors, taking part in a trading system that moved food and goods between southern Mexico and the southwestern U.S.


A Sonoran Oasis Food security in the Desert

Summary Currently, Ajo is part of a global food system, while local gardens provide just occasional fruit and vegetables. Yet recently, Ajo has seen modest, yet enthusiastic, growth of its budding local food system through its farm stand, community gardens, pomegranate orchard, and more. Though Ajo’s local system cannot provide some of the foods that residents currently enjoy, like coffee, and chocolate, it can provide much more than it currently does; it can provide a variety of foods, an enhanced economy, connections to regional culture, and greater self-determination. The traditional Tohono O’odham food system shows that a global system does not have to be the dominant supplier of arid land-adapted foods like flour, beans, squashes, corn, and greens. Local and regional foods, supplemented by global sources, could create diversity, resiliency, freshness, and choice—leading to more food security.

Land requirements Comparing models The amount of land required to feed one person for one year in southern Arizona is difficult to determine. It has been estimated that traditional Tohono O’odham agriculture and wild-harvesting would require 4 acres; modern conventional agriculture would require between 0.5 and 1.2 acres; and Ecology Action Biointensive organic agriculture would require 0.05 acres (Lancaster 2011). Each approach has associated environmental impacts, required levels of labor input, and particular crop palettes. These numbers are also not reflective of the current dietary intake of Ajo’s residents. A study by Christian Peters aimed at determining agricultural carrying capacity based on diet included many of these variables, and also showed that “increasing meat in the diet increased per capita land requirements” (Peters et al 2006, 145). Dietary modification may be required to minimize the amount of land required, and the associated environmental impacts from agriculture and livestock. The Peters study suggests that the optimum quantity of meat in a diet should be limited to the amount of marginal lands appropriate for grazing or pasture that are not otherwise suited for agricultural purposes (Peters et al 2006). A detailed survey of Ajo’s dietary intake is recommended before calculating how much land is required to feed Ajo. See Appendix D for further suggestions and resources for these calculations.

Biointensive Agriculture

The goal of Ecology Action Biointensive agriculture is to produce the maximum amount of food per unit of land. Biointensive agriculture is reportedly able to grow up to six times more food than conventional methods, using up to 88 percent less water. This system uses compost, dense plant spacing, and the careful selection of companion plants to obtain high yields, while simultaneously reducing fertilizer dependence and energy use. With a two-fold focus on growing food and capturing carbon to enhance soil fertility, Biointensive agriculture offers a method for producing more food with less space and fewer inputs. Visit for more information.

A Sonoran Oasis Land Requirements


Water in the Desert Water, the most limiting factor in desert agriculture, has been a subject of intense focus in the southwest as increasingly heavy demands are placed on dwindling reserves. In Arizona, continued mining of groundwater is disrupting desert hydrology and ecosystems. When exploring the possibility of agricultural expansion in the Sonoran Desert, the implications for this already compromised resource must be considered. Aquifer Depletion and Availability The Basin and Range aquifer system supplying Ajo extends underground over 200,000 square miles, and is composed of contained pockets of water within a network of saturated and highly

permeable sand and gravel called basin and fill (Musgrove 2005). Though seemingly vast, water levels in portions of this aquifer have been significantly depleted. The city of Tucson diverts Colorado River water 336 miles to supplement high demand due to draw down, damaging riparian habitat in the process (Central Arizona Project 2011). Ajo and the farming town of Gila Bend, forty-three miles to its north, share the Lower Gila Basin of the Lower Colorado Watershed. Ninety-eight percent of groundwater in the Lower Gila Basin is used for agriculture resulting in “cones of depression” in Gila Bend—sinkholes which formed after too much water was extracted (Arizona Water Atlas 2011; Arizona Department of Water Resources 2011).

Basin and Range Aquifer System

The Basin and Range aquifer system extends across seven states.


A Sonoran Oasis Water in the Desert

A new solar power facility in Gila Bend may require as much as 60,000 acre-feet per annum (AFA) of groundwater per year for cooling, according to hydrologist Larry Onyskow, possibly exceeding the estimated groundwater recharge rate of more than 9,000 to 88,000 AFA (not including withdrawals for other uses) (Arizona Department of Water Resources 2011). Whether this operation, or other uses, could have an impact on the long-term water supply for Ajo is unknown (Onyskow 2011). Nonetheless, 100-246 million acre-feet of groundwater may be stored in the Lower Gila Basin (Arizona Department of Water Resource, 2011). Data on the distribution of groundwater throughout the entire area is not readily available, particularly for the 1220-square-mile Ten Mile Wash sub-basin (USGS Unit

15070202), in which Ajo is situated. Even with general data on the Lower Gila Basin, determining groundwater availability for a specific location in the sub-basin would require further scientific research, possibly including the drilling of test wells (USGS 2010). During the height of mining operations, 13 million gallons of water per day were reportedly used, causing some aquifer draw-down (Arizona Department of Water Resources 2011). Due to the need for significant volumes of water for their industrial processes, it is possible that Freeport-McMoRan may have more data regarding groundwater availability in the area (Arizona Department of Water Resources 2010).

The Lower Gila Sub-Basin drains to the Gila River.

A Sonoran Oasis Water in the Desert


Water in Ajo is pumped from the wells north of town and held in two storage towers near the mine pit. Wastewater is deposited on top of the tailings dam east of town. Highway 85

Tailings Dam


Arroyo Utility Co. Well Mine Pit Water Tower Wastewater Treatment


A Sonoran Oasis Water in the Desert

Private Wells A subsidiary of Freeport-McMoRan, Ajo Improvement Company (AIC), owns two wells that supply 1100 Ajo households with water (AIC 2011). AIC also sells water to two other utility companies, Five Acres Water Company and Arizona Water Company, which then resell the water in different geographic territories within Ajo. Rates between the companies vary, though discounts are available for large-volume consumers. There are also private wells throughout the Ajo area that draw on the aquifer. It is unknown to what extent these wells are functioning, but well owners may have access to a low cost supply of water, though without the benefit of having the water companies filter out naturally occurring contaminants. The site specific availability of water for new wells cannot always be predicted. An observation well must first be drilled to determine the suitability of a well site. Recharge rates must equal or exceed extraction rates for a well to be sustainable. This testing can add more cost to an already expensive drilling process. Subsurface Groundwater Rights While wells are privately owned, subsurface goundwater is not. Arizona law allows for “first in line, first in use,� as long as others dependent upon the same system are not negatively impacted (Arizona Department of Water Resources 2011). Therefore, wells may be used for agricultural production unless there are negative consequences for others using the same water source. Water Quality Water in the Ajo area is of poor quality due to high levels of naturally occurring arsenic and

fluoride, which the utility companies filter out to state regulated levels (Consumer Confidence Report). Owners of residential wells may or may not filter their water. That crops may uptake arsenic from water must be a consideration when using unfiltered water for growing food. There is no documented mining-related contamination of the aquifer near Ajo, though private wells not used for the public drinking supply may not have been tested. The naturally occurring arsenic and fluoride and the presence of up to seventy potential brownfield sites in Ajo suggest that testing before use on edible crops would be prudent. Due to geothermal heating, the water temperature is 107 degrees when extracted from the aquifer. Some cooling may occur during water transfer and storage, though temperatures at the tap remain high. Whether this temperature can affect plant growth is unknown. Surface Water The arroyos and stream channels that fan out over the landscape remain dry most of the year, flooding when the monsoon rains come in July and August. The seasonal surface water can be legally used, though it is illegal to draw surface water from a perennial water source (of which there are none in the Lower Gila Basin). Surface water is always present at the bottom of the 1.5 mile wide mine pit. The volume, depth, quality, and recharge rate of this water is unknown. To test the water, Freeport-McMoRan would have to authorize access to the pit, presenting possible legal issues. It is unknown if assessing and obtaining this water would be feasible.

A Sonoran Oasis Water in the Desert


It is unclear whether drawing on it for agriculture in Ajo is sustainable. Perhaps it is safe to assume that the less dependent upon a single unquantified source, the more secure and stable a community will be. Regional deficiencies in the water supply resulting from the careless or ill-advised mining of the aquifer for agriculture and other uses indicate that conservation and the use of alternative water sources could reduce the risk of further degradation of this imperiled resource. Ak-Chin Agriculture Traditional methods of dryland agriculture are practiced in arid environments around the world. In the Sonoran Desert, the Tohono O’Odham people use ak-chin agriculture to manage a scarce and variable water supply to grow food. Ak-chin water management techniques involve planting drought-adapted crops at the mouths of washes. A network of irrigation channels with subtle gradations of elevation disperse water over large planting areas (Nabhan 1987). Additionally, catchment basins collected water for later use. Perfected over generations, the efficient use of water enabled people of the region to produce food in an extremely arid

environment. “The area in which the town of Ajo is now located was important to the Tohono O’odham [Hia C-ed O’odham] Native Americans who used water from a series of potholes they called Mu’i Wawhia Moivavi meaning ‘Many Wells’” (Pima County 2009).

Ancient Knowledge

Today this ancient knowledge is imperiled as the number of traditional practitioners dwindles. In spite of the obstacles, a small group of people has dedicated itself to perpetuating and reviving the traditional agriculture of the Tohono O’odham people. In addition to the efforts being made on the Tohono O’odham Nation, a garden in Ajo is being constructed with the guidance of tribal elder Clifford Pablo. Saving this vital knowledge has cultural and health implications for the Tohono O’odham and Hia C-ed O’odham people, and has the potential to inform others how to live sustainably in this sensitive environment. Maintaining and expanding an understanding of ak-chin can increase adoption of regionally appropriate agricultural methods to the benefit of the environment, and subsequently all regional residents. In Tucson, ak-chin and other traditional dryland water management practices, like earthworks, are being adapted for use in an urban environment. Water is being harvested, reused, and conserved on a county-wide basis as the need to reduce stress on the aquifer and Colorado River supply becomes more urgent.

Modern ak-chin farming at Cowlic Farm on the Tohono O’odham Nation.


A Sonoran Oasis Water in the Desert

Earthworks During seasonal rains, stormwater floods streets, moving rapidly through the landscape. Impervious paved surfaces prevent absorption and increase the velocity of the water, which can cause flooding, exacerbate erosion, and flush pollutants into storm drains, thus contaminating waterways. By slowing the flow and keeping water on-site longer, velocity decreases and absorption increases. Earthworks, like berms and curb cuts, can direct the flow of stormwater into swales planted with native vegetation and fruit trees to soak up the water and reduce flooding, create habitat, and provide food. Due to the possibility of water contamination, it is recommended that street runoff be used only for tree crops (Lancaster 2011). Replacing impervious concrete and asphalt with permeable surfaces allows percolation into the soil, increasing the water available to plants. Earthworks can also be used to channel runoff into gardens and landscaping.

Curb cuts in Tucson direct the flow of stormwater runoff.

Community Rainwater Management

The Tucson-based Water Management Group (WMG) promotes and teaches water management techniques for the prosperity of people and the environment. WMG believes “communities develop in concert with their environment, and the success of development is measured by the health of ecological systems, the prosperity of people, and the strength of communities” (WMG 2011). Working on the neighborhood level, it is possible to use communal tanks to store roof runoff and stormwater. With a cohesive neighborhood management plan, the benefits and the investments could be shared, including storage tanks, labor, and expertise.

Swales with native plants collect runoff.

Rooftop Collection Can Capture Rainwater for Food Production Rainwater can be collected off roofs and directed to where it is most beneficial, or stored in tanks for later use. A storage tank might be an option for those seeking to regulate the release of the rainwater over time, but may not be cost effective or practical. A tank at the Ajo Community Garden Consortium’s garden at the Curley School Campus is used to collect rainwater, but the tanks are emptied within a few weeks due to irregular rainfall. Unfortunately, an asphalt shingled roof is not suitable for harvesting water due to the A Sonoran Oasis Water in the Desert


trees (AIC). Plans are underway to find an alternative method of disposal by next year because pumping the wastewater is expensive and has the potential to leach contaminants through the tailings into groundwater. A clarification system, possibly including a large evaporation pond, will be added—bringing water up to a B-grade level that is suitable for agriculture.

Rooftop rainwater may be directed to vegetation and collected in a storage tank for later use.

potential for contamination from chemicals in the asphalt. But the runoff could still be used to grow vegetation that is not for consumption or to serve as shade trees. Greywater Reuse Water that has been used in the kitchen, shower, sink, or laundry is called greywater. On average, it is estimated that a person disposes of 6,250 to 25,000 gallons of greywater each year (Gulyas 2002). Greywater reuse requires limiting the use of certain household chemicals that may be harmful to plants or people. Simple diverters can be used to rotate which plants receive water. Legally, greywater may only be used to water vegetation that is not for consumption and tree crops (see appendix A for more information on Arizona greywater laws). Clarified Wastewater for Food Production Ajo Improvement Company (AIC) which owns the sewage treatment facility, treats over 46 million gallons of Ajo’s wastewater per year, and pumps it to the top of the New Cornelia Mine Tailings Dam to a stand of non-native salt cedar


A Sonoran Oasis Water in the Desert

Water in the desert is a valuable commodity and clarified wastewater is used for agriculture in Tucson. Informal conversations with AIC representatives indicate a willingness to consider contracting for longterm use of some or all of the clarified wastewater. Time may be limited to pursue this option, because of the need to move forward new treatment options. Using the clarified wastewater—with arsenic and fluoride filtered out—for food production could represent a significant value in water cost savings. This volume of wastewater could be used on a larger scale project such as a commercial farm or a constructed wetland. Tucson’s constructed Sweetwater Wetlands purify water while providing wildlife habitat, hiking trails, and educational facilities. Could food production be integrated into a constructed wetland? Freeport-McMoRan has a clearly stated company policy of promoting environmental stewardship, water conservation, and community development. Projects that benefit Ajo, which has been economically challenged since the mine closure, may represent an opportunity for the company to generate positive publicity and participate in the revitalization of Ajo through agriculture.

Urban Oasis Case Study: Brad Lancaster

Ajo has the potential to benefit from the recent swell of interest in innovative water management techniques being employed elsewhere in Pima County. Nearby Tucson is home to Brad Lancaster, author of Rainwater Harvesting for Dry Lands and Beyond, Volumes 1 and 2, who has adapted traditional dryland agricultural principles for his urban environment. Lancaster has demonstrated the efficacy of simple rainwater harvesting techniques and greywater management to significantly reduce his dependence on external water sources, save money, and generate many other benefits.

Brad Lancaster holds a jar of olives grown with harvested rainwater.

By channeling, capturing, and filtering rainwater from the roof of his 1000-squarefoot house, Lancaster is able to grow a productive garden and shower for free. Lancaster’s household greywater, and the outflow from a washing machine shared by neighbors, is diverted to lush fruit trees. Additionally, Lancaster has altered the public right-of-way in front of his house by making cuts in the curb that allow storm water to flow into swales. These swales, planted with edible and native plants, provide habitat for wildlife, food, and shade as well as floodwater filtration and flood

control. All totaled, Lancaster harvests over 100,000 gallons of water a year and purchases only 20,000 gallons to maintain a household of three, as well as the community washing machine. What started as an individual effort has quickly expanded to include much of Lancaster’s street as well as other neighborhoods. This model is becoming accepted as a citywide and countywide standard, leading to the creation of tax incentives to offset installation costs, relaxation of the county water harvesting regulations, and permission to cut curbs. Lancaster’s success is directly linked to his community based approach and firm commitment to interacting and communicating with his neighbors. If Ajo is to use a sustainable approach to growing food locally, then any methods that minimize aquifer dependence should be considered. Brad Lancaster has shown how low cost adaptations to existing structures can yield tremendous payoffs for the environment and quality of life.

Community washing machine diverts greywater to fruit trees.

A Sonoran Oasis Water in the Desert


Aquaponics Case Study

As a Ph.D. candidate at the University of Arizona, Jason Licamele conducted extensive research on aquaponics as a potentially sustainable food source.

Farming fish and vegetables at an aquaponics facility in Milwaukee Photo Credit: Wikimedia Commons

Aquaponics is a Water-Efficient Way of Growing Food The developing field of aquaponics, a combination of aquaculture (fish farming) and hydroponics (soil-less agriculture), offers promising potential for food production and economic growth (Diver 2006). In this closed loop system, the wastewater of organically fed fish fertilizes the hydroponically grown vegetables. After the nutrients in the water have been used by the plants, the water is returned, cleaner, to the fish tank.

The University of Arizona system used four 12,000-gallon tanks in a 2,500-square-foot greenhouse to produce between 1,058 and 2,116 pounds of tilapia and between 29,348 and 58,696 plants (Pangburn 2009). Species of fish other than tilapia may be grown, and vegetables and herbs such as lettuce, tomatoes, and basil thrive in this system. This method uses space ten times more efficiently and water 500 times more efficiently than conventional agriculture (Licamele 2009). Only one percent of the total volume of water must be replaced weekly. This system has enormous potential to provide a sustainable food source in marginal environments lacking quality soils and water resources. Market research at the University of Arizona has indicated that a high-end niche market exists for these organic products in urban centers (Licamele 2009). Licamele now runs Fish Farmacy, a consulting firm that helps design and setup aquaponics and other related systems including wastewater treatment and constructed wetlands (Pangburn 2009,

A simple aquaponics system


A Sonoran Oasis Water in the Desert

Research at the University of Arizona has shown that aquaponics can be a viable option in the Sonoran Desert and could provide economic and nutritional benefits. The set-up costs depend on the scale of operations and require further research.

Oases of Food & Diversity: Quitovac & Quitobaquito “The richness of biota at Quitovac has provided its inhabitants with a diversity of foods, medicines and ceremonial paraphernalia, over and above any cash crops produced there.” (Nabhan et al 1982) For centuries, the Hia C-ed and Tohono O’odham managed the Quitovac oasis to provide food, while supporting diverse plant and animal communities. Sited at a series of natural springs in Sonora, Mexico, Quitovac’s cultivated fields, orchards, hedgerows, and other productive lands were maintained as a sustainable agro-ecological system. The O’odham enjoyed a diverse array of cultivated and wild-harvested foods, hunted game, extracted medicines, and crafted ceremonially important items from the system. Since 1981, when much of the surrounding land was cleared and leveled for modern irrigated agriculture, the diversity of the system has decreased significantly. According to ethnobotanist Gary Nabhan, the O’odham managed Quitovac “in ways that encouraged diversity, resulting in benefits in environmental stability or food abundance and reliability.” Thirty-nine bird species, fourteen mammal species, and 138 plant species at Quitovac have been documented. Though only seventeen of the plant species were intentionally cultivated, another fifty-nine species adapted to human disturbance patterns. By integrating agriculture with animal and plant habitats, the O’odham were engaged as stewards who managed the health of the whole ecosystem. Less than thirty-five miles away in the U.S., Quitobaquito was once a similarly diverse and productive oasis managed by its residents. Quitobaquito shares many

geographic similarities with Quitovac, including its climate and spring-fed lagoons, but differs primarily in its management history. Quitobaquito’s diversity and productivity has decreased under National Park Service (NPS) management that has focused on preservation, in contrast to the land ethic it replaced. NPS authorities failed to understand the interdependent relationship of the agricultural land management practices and the wild diversity there. Without that dual purpose management, many cultivated plants withered, some uncultivated species ceased to regenerate, and rare wildlife habitat was lost. “The biggest challenge for the human species is to find ways to use nature without destroying it. This means moving beyond preservation by creating a real working relationship with the landscape,” states M. Kat Anderson (2006), the USDA’s national ethnoecologist. Quitovac is an example of an agricultural ecosystem managed to encourage the diversity of elements in the system and thereby increase its stability and productive abundance. Such diversity supports multiple ecosystem functions such as pollination and pest control. “In agricultural situations, there is clearly a positive correlation between plant diversity in fields, and stability with regard to vulnerability to animal pests” (Nabhan et all 1982). Perhaps lessons learned from this history can help create a productive, integrated agro-ecological system in Ajo. By directing clarified wastewater through canals and natural washes, it may be possible to cultivate an oasis inspired by Quitovac, beneficial to plant and animal wildlife, and people. Oasis ecosystems like those historically at Quitovac and Quitobaquito are rare and valuable, says Nabhan.

A Sonoran Oasis Water in the Desert


Quitobaquito oasis still supports a diverse ecosystem of many rare and endangered plants, though not as many as it once did under O’odham cultivation. Photo Credit: National Park Service

“It may be worth considering that diverse agricultural habitats, including certain ones maintained by native American farmers for centuries, are also now endangered. It is unlikely that one could find environments more rare or more vulnerable that those found in the desert oases like Quitovac or Quitobaquito. Their loss will affect not only the bird and mammal populations sustained by them, but may impoverish the life of the human community as well.� (Nabhan et al. 1982)


A Sonoran Oasis Water in the Desert

Wildlife Depend on Water As much as 85 percent of wildlife species in Arizona (many of which are endangered), require riparian habitat at some point during their lifecycle (Pima Association of Governments 2003). Currently, 90 percent of riparian habitat and perennial water sources in the state have become degraded due to the human use of surface and groundwater sources. The reintroduction of water would attract wildlife, but need not preclude farming (though fencing may be required to protect certain crops). Hia C-ed O’odham agricultural practices at Quitovac and Quitobaquito accommodated wildlife habitat without compromising productivity. For more information about riparian dependent wildlife, see Appendix B. Summary The future demands on the aquifer system supplying Ajo are unknown, but water shortages in other parts of Arizona and New Mexico have had serious consequences for agriculture, resulting in the closure of many farms (Nabhan 2011). One cannot assume that aquifer recharge rates will be sufficient for sustainable food production. It is unclear whether it is appropriate to draw aquifer water—and how much—for agriculture. Certainly, water conservation and reuse will reduce stress on Ajo’s aquifer.

Sonoran Desert resident, the rare cactus ferruginous pygmy-owl Photo Credit: Wikimedia Commons

A Sonoran Oasis Water in the Desert


Soil & Vegetation Soils & Vegetation

Soil is an important factor in plant growth, and therefore has implications for agricultural production. What if agriculture in Ajo honored the desert’s natural soil and vegetative patterns to increase food production? Ajo’s Mineral Wealth The geologic landscape around Ajo is the product of 15 million years of tectonic plate movements that have Bedrock Gravel Sand Loam stretched apart the earth’s crust, revealing layers of stratified rock and allowing magma to flow to the surface Erosion causes the richest soils (loam) to accumulate in floodplains. in widespread eruptions. This complex history contributes to the mineral salinity, and other soil traits. As these mountain wealth and unusual landscapes around Ajo. In formations have eroded, the valleys between addition to supplying vast amounts of copper, them have accumulated layers of mixed the mineral deposits at Ajo are one of only alluvium. These eroded materials are three sources of papagoite in the world and continually transformed by plant and animal where the mineral ajoite was discovered, which life, and by climate. A site’s topography greatly was named after the town. determines the types of soils that form and accumulate there; where rainwater slows in the bottom of valleys and where washes fan out are the finest particles and the richest soils.

The copper ore Ajoite was first found in Ajo. Photo Credit: Wikimedia Commons

The mountains around Ajo are composed of igneous, metamorphic, and small outcrops of sedimentary rock. These rocks form the parent material for the soils around Ajo, and thus determine the composition, alkalinity (pH),


A Sonoran Oasis Soil & Vegetation

Poor Soil Quality Represents a Challenge The Ajo area contains twenty-one soil types, only one of which is considered by the Natural Resources Conservation Service (NRCS) to be “prime farmland soil, if irrigated.” The soils within town vary from sandy loam to extremely gravelly sandy loam; from nonsaline to moderately saline; and from somewhat well drained to excessively drained. Human activity has disturbed soil structure, which is considered good quality when water, air, roots, and microorganisms can move through the root zone (Johnson 2008). The use of heavy machinery, tilling, and monocropping is

Highway 85


Why Tucson Mexico Only one type of Ajo’s area soils is considered prime for farming by the NRCS.

discouraged by the NRCS because it can reduce soil structure and plant productivity (Johnson 2008); instead, crop diversity and rotation is recommended. The soils in the region are typically highly alkaline, partially due to large amounts of dissolved calcium carbonate. High alkalinity reduces the availability of nutrients to some plants, and thus reduces growth and yield. Applications of manure, compost, or other amendments help reduce soil alkalinity. Calcium carbonate, along with other minerals, often forms a solid hard-pan layer. Such layers can cause drainage problems and restrict root development. They may be shattered or ripped by subsoil plowing, depending on their depth and thickness.

High levels of sodium, chloride, boron, lithium, and other elements in the water supply require proper irrigation techniques to prevent toxic concentrations of these salts from accumulating in the soil (Johnson 2008). Adding organic matter or subsoil plowing to open soil structure, followed by watering can help remove or leach salts below the root zone (Johnson 2008). The Desert Matrix Includes Many Edible Plants Some plants are more adapted than others to handle high salinity conditions, and these plants could offer reliable and low management alternatives to conventional crops. Perennial plants dominate the natural desert vegetative matrix around Ajo; emergent saguaro cactus tops a lower canopy of palo verde, mesquite, and ironwood trees. A shrub layer of creosote A Sonoran Oasis soil & Vegetation


Testing For Soil Contamination

A quick “windshield survey” done by Pima County identified as many as seventy potential commercial brownfield sites within Ajo. Many of these sites had former uses as gas stations, auto repair shops, or dry cleaning facilities—uses which may have left heavy metals and other toxins in the soil. The brownfield designation makes free soil testing available to any landowner who suspects possible contamination. The Arizona Department of Environmental Quality (ADEQ) runs a streamlined process called the Voluntary Remediation Program, which “allows property owners, prospective purchasers, and other interested parties to investigate or clean up a contaminated site in cooperation with ADEQ” (Pima County 2009). If contamination is found, non-profit organizations and government entities may apply for further grants for remediation expenses. Freeport-McMoRan contracted Shaw Environmental & Infrastructure to test properties in town for minerelated soil contamination. They hope that testing will reveal any possible patterns that might indicate the spread of contaminated debris by wind or flood waters. Though no patterns have been found, their reports to the community have indicated that 4 percent of properties tested positive for contamination, including arsenic in the Curley School courtyard. Upon completion of testing, FreeportMcMoRan agree to remove and replace contaminated soils (Ajo Copper News 2008).


A Sonoran Oasis Soil & vegetation

bush, and cholla and prickly pear cactus reach above an herbaceous layer of perennial grasses and some seasonal annuals and wildflowers (GAP Vegetative Cover Analysis). The O’odham have a long tradition of gathering the desert’s seasonal bounty from each vegetative layer; saguaro cactus fruit are eaten fresh or made into preserves, mesquite pods are ground into flour, and wild greens are gathered after rains. Perennial plants dominate the desert cover because their extensive, established root systems have adapted to the scarce water and nutrients, while ephemeral plants will only grow and bloom en masse for a short period if the conditions allow. The Tohono O’odham cultivated some annuals that also adapted well to the stresses of heat and water scarcity, like tepary beans and sixty-day corn. Area O’odham farmers “were consummate plant breeders” (Sheridan 2006, 35) and developed many varieties of hardy, dependable crops. “These nutritious crops deserve to be revived as mainstays of human diets, and not treated as passing curiosities. These cultivated foods are rich in taste and nutrition, yes, but they are also well adapted to the peculiarities of our land” (Nabhan 1995, 193). Using these desert-adapted plants to increase food production would require less intense soil modifications than conventional crops. But it isn’t only plants’ adaptations that allow them to grow well. Practiced by the Tohono O’odham, ak-chin farming takes advantage of natural systems to nourish the soil and increase plant yields.

Arizona Mesquite Company Crops to Fit the Land

Mark Moody realized what he had found when he accidentally unearthed several manos y matates under centuries-old mesquite trees he was clearing from his land. He had been on a quest for a sustainable, indigenous desert crop requiring little water and no chemical inputs. The discovery of these stone relics on his land, used by native peoples to grind mesquite pods into meal, made it clear to Moody that the crop for which he searched was the same revered by peoples of the Sonoran Desert throughout history, but largely overlooked by modern society: mesquite.

delicious flour for human consumption. The mesquite lumber also has value for fine woodworking and produces fragrant smoke that can be used to flavor foods. Moody founded Arizona Mesquite Company in 2005 and pioneered mesquite cultivation, as there were no mesquite nurseries or farms existing at the time. The Bouse, Arizona, farm currently has seven acres dedicated to a velvet mesquite (Prosopis velutina) orchard. Arizona Mesquite is also selectively breeding mesquite for desirable crop qualities.

Although the establishment of mesquite plantings may be difficult, Moody insists Mesquite is a that growing ubiquitous tree and producing in the deserts of mesquite is easy. the Southwest. It During the first two is well adapted to years, plantings arid conditions, benefit from shade with roots that screening, drip can reach over irrigation, and 150 feet deep Manos y Matates sketch by Mark Moody protection from in search of water jackrabbits and other (Sosebee 1987). It can herbivores. The management intensity also thrive on water that is too saline for declines over the next eight years, and there many other plants. As a legume, mesquite is is subsequently little maintenance after the adapted to sequester atmospheric nitrogen, tenth year. thus creating fertilizer for itself and its neighbors. Mesquite is considered a nurse It may take up to ten years for mesquite to tree, improving the soil around it through begin to produce a substantial yield. Other the mulching effects of its fallen leaves, and crops, such as chia, amaranth, sorghum, creating a microclimate favorable to other corn, squash, prickly pear cactus, or beans plants. may be interplanted with mesquite. The shade and rich mulch provided by the The pods of the mesquite are highly mesquite will help with the growth of other nutritious with high levels of micronutrients crops. When honey bees have access to the and protein, low glycemic index, and no pollen of the mesquite flower they produce gluten (Zolfaghari 1984). The seed pods a fine artisanal honey. are valuable wildlife food, can be fed to livestock as fodder, or processed into a

A Sonoran Oasis soil & Vegetation


Moody estimates that a 1000-acre mesquite farm would provide 100 jobs for four years, as workers establish the farm infrastructure, and plant and thin trees (personal communication 2011). After the fourth year, a farm this size could support 50 full-time workers employed in maintenance, harvesting, and administration. The infrastructural requirements would include starter greenhouses, propagation space, irrigation, and equipment to mill the pods into a salable flour. Mesquite can be planted at a 10 foot spacing, with every other tree thinned out after the seventh year for desirable lumber. Moody believes that mesquite can be grown on a residential scale. A 600-square-foot backyard can support two mesquite trees as well as corn, melon, beans, and other crops. If the trees are heavily mulched, the need for irrigation may be dramatically reduced. If home-grown mesquite flour is to become viable, there needs to be a community milling facility to process the pods. The non-profit Desert Harvesters of Tucson brings a mobile hammer mill, obtained through PRO Neighborhoods grant funding, to various milling events around southern Arizona. Desert Harvesters may serve as a partner or a model for establishing a similar program in Ajo. When asked about the challenges of farming mesquite, Moody responded that customer lack of familiarity with the product was the biggest challenge. However, considering the low input requirements of this desert-hardy tree and its high value nutritious food crop, mesquite may be a wise investment.


A Sonoran Oasis Soil & vegetation

Typical vegetation around Ajo includes cholla and saguaro cactus, mesquite, palo verde, and other perennial plants.

Tohono O’odham Ak-chin Farming Builds Soils By Capturing Runoff As stormwater runs through washes and streams, it gathers leaf litter, dung, and other organic materials from the desert floor, and carries them in the torrent. By directing streams and strategically planting crops at the mouths of washes, ak-chin farmers captured the runoff water and the organic matter it carried. As Gary Nahban wrote, “The elegance of runoff farming is that when a field receives a fresh flush of water, it is simultaneously being recharged with nitrogen. A surge of crop growth is inevitable� (1987, 128).

The Sonoran Desert’s extreme heat causes rapid oxidation and depletion of organic matter from the soil, resulting in a typical organic material content of less than 1 percent (Johnson 2008). However, as the O’odham demonstrated in their ak-chin fields, organic matter can be built-up. The organic content of centuries-old ak-chin fields have been measured at upward of 5 percent, which is comparable to good U.S. Grain Belt soils (Nabhan 1987).

Nurse Trees One soil building technique, borrowing from Sonoran Desert ecology, is the use of nurse plants. Nurse plants can be trees, shrubs, or grasses. These plants provide shade, which reduces soil temperature and desiccation of young plants. Nurse plants increase organic matter through their leaf litter, help retain soil moisture that might otherwise drain quickly through sandy or gravelly soils, and capture windblown dust and organic matter. Some also self-fertilize by fixing nitrogen in the soil, and can help moderate soil alkalinity and salinity.

Nurse trees build soil fertility.

A Sonoran Oasis soil & Vegetation


Establishing Desert Trees: A Tall Order

The environmental extremes of the Sonoran Desert prove a challenge even for well established plants. Recent transplants that have yet to develop roots have even more difficulty. Further, traditionally potted plants are grown in wide, shallow pots that inhibit deep root development. Transplanting such rootbound plants require special care and frequent irrigation. Tall pot technology, vertically oriented tubes typically thirty inches tall by six inches in diameter, encourages proper root development, enhancing transplant survival and decreasing costs. Tall pot methods are not new—they have been used in Europe for several decades— but they have been gaining recognition for their use in the arid southwest. Tall pot methods have been used successfully for projects in Joshua Tree National Park and across Maricopa County, Arizona. When transplanting nearly 2000 native trees with tall pot technology in Phoenix, the Flood Control District of Maricopa County (FCDMC) saw a survival rate over 95 percent. Trees with healthy root systems require less irrigation for establishment. Coupling tall pot technology with time-released water capsules, FCDMC has reduced the cost of successfully establishing trees to an average of $100 per tree. “Water has become a worldwide commodity especially in arid regions where irrigation is extremely challenging. The good news for vegetation and revegetation projects is that tall pot technology creates long term sustainability. The method is cost effective, and gives trees a healthy start to thrive and survive” (Lechner et al 2011).


A Sonoran Oasis Soil & vegetation

Shade cast by nurse plants has been observed to reduce the maximum soil temperature two centimeters beneath the surface by over 50 degrees F, providing a microclimate suitable for seedling establishment (Nobel 1989). The soil beneath a nurse plant contained 66-90 percent higher levels of nitrogen, substantially higher levels of potassium, and lower levels of sodium when compared to bare ground (Nobel 1989). Similar studies identify mesquite, palo verde, acacia trees, desert ironwood, and creosote bush as nurse plants (Vandermeer 1980, Arriaga 1993, Nabhan et al 2000). Many nurse trees also provide an edible crop and may be used as part of a rotational polyculture: nurse trees pioneer farmland and eventually give way to slower growing food crops. Nurse trees can help establish fruit orchards and slow-growing crops while improving conditions for understory crops. Mulching can also increase organic matter and nutrients, while also conserving water. Potential sources of mulch already exist within the current Ajo waste stream; food scraps, yard waste, leaf litter, and woody debris could be turned into mulch-able compost, but instead are landfilled. Composting Can Help Turn Organic Waste Into Soil Nutrients By capturing organic waste, composting can help close a nutrient cycle, increase food production, and reduce dependency on fossilfuel-based fertilizers. In order to create the appropriate biological and chemical conditions for composting to occur, a compost pile requires certain inputs and structure. A properly constructed compost pile will speed up the decomposition process— generating heat in the process. The optimal

carbon to nitrogen ratio is approximately 25:1 (Haley 2009), otherwise known as “browns to greens.” Material high in nitrogen such as manures, grass clippings, and vegetable waste are layered with materials high in carbon like straw, wood chips, and shredded newspapers. On a smaller scale, piles should be around 3’-5’ in height and depth, and can be placed in secure bins; larger operation typically use long windrows. Since air and water are essential to creating healthy, aerobic composting conditions, piles must be turned regularly to maintain oxygen circulation, and an appropriate moisture level.

Nitrogen Sources Around Ajo The Border Patrol stables just ten minutes down highway 85 in the small town of Why represent a potential source of free manure. Their twentytwo horses produce around 200 tons of manure annually that the Border Patrol currently pays to have trucked away. A conversation with Border Patrol agents revealed that they would happily give away the manure to anyone willing to pick it up, as long as it isn’t sold. “Just give us a call and bring a truck and a shovel,” the agent said (Personal Communication 2011). The Why-Ajo-LukevilleDevelopment group (WALD) leases land for a rodeo grounds and roping arena in Ajo Regional Park (which is managed by Pima County Natural Resources, Parks & Recreation). Their lease precludes the possibility of food production on site, but does not eliminate the possibility for composting.

Organic waste transformed into compost with the help of worms can be used to nourish vegetable seedlings. Photo Credit: Wikimedia Commons

Composting can occur at the residential or the municipal level. Many communities routinely collect and compost vegetable and yard wastes, returning finished compost to residents for free, or at a reduced rate. Ajo has several sources for large volumes of nitrogen and carbon that could be composted to provide structure and nutrients for the poor desert soils.

Though the amount varies depending on how many animals are being boarded, they typically produce about one pick-up truck full of manure per month, according to Tony Montez, who manages the park for WALD. Conversations with Mr. Montez have indicated that removing the manure might be mutually beneficial; WALD would get help managing their on-site waste, and ARFP members would get a source of compost material.

Ajo Unified School District and restaurants could also be a reliable source for food scraps during the school year.

A Sonoran Oasis soil & Vegetation


Mycorrhizal Fungi to Increase Crop Productivity Two other generally overlooked possible soil amendment are mycorrhizal fungi and rhizobacteria, which have been documented to aid in healthy plant growth (Bashan et al 2005). Such organisms form beneficial relationships with plants, breaking down organic matter and minerals into accessible forms, retaining moisture, and providing defense against other organisms. Such microorganisms are essential to the functioning of natural ecosystems, yet are largely ignored in modern agricultural operations. Inoculation of crops with such microorganisms may help increase plant health, while decreasing the need for other soil inputs.

Carbon Source Availability is a Limiting Factor for Large-Scale Composting The plentiful nitrogenous materials around Ajo need to be balanced by large amounts of carboniferous materials. Though there are no similarly regular supplies of carbon materials, there are some options that may be explored. Newspaper is a highly compostable, carbon-rich material. Recycled past issues of the weekly Ajo Copper News could be collected town-wide and composted. Another potential source of carbon is cardboard from restaurants, Olsen’s IGA supermarket, and the convenient stores and dollar stores in town. It is recommended to shred the cardboard before adding it to a compost pile, in order to aid in breakdown. Large-scale and municipal-level operations typically compost in windrows turned by a tractor. Windrows are generally regarded as one of the simplest and most space-efficient


A Sonoran Oasis Soil & vegetation

methods for large-scale composting, but might not be appropriate for all areas of Ajo. Zoning Regulation Restrict the Placement of Composting Sites According to Arizona State Law (Title 9, Section 9-462.01, Subsection G) large-scale agricultural composting cannot be conducted within 1,320 feet of existing residential homes, unless on farmland or land “leased in association with farmland.” Pima County zoning law also restricts placement of large scale composting facilities near residential areas, but places no restrictions on backyard composting. A seemingly ideal location for compost windrows is at the Ajo Town Landfill. Since residents already bring their organic materials there, it would be convenient to expand the landfill to allow for a separate section for organic materials and yard waste. Dave Eakers, Pima County Deputy Director of the Solid Waste Division, agreed that the landfill would be a logical place for composting, but suggested that it may not be possible due to space restrictions. (The landfill was expanded in 2009.)

In addition to household trash, some of the landfill’s contents are organic material that could be composted.

The land immediately surrounding the landfill belongs to Freeport-McMoRan; the land is not currently being mined. It is therefore recommended to consult with FreeportMcMoRan to expand the landfill to accommodate space for delivering organic materials. It is difficult to determine the size of the windrows or the plot of land needed to support a composting operation in Ajo, but such specifics can be calculated by using a worksheet from the Highfields Center for Composting in Hardwick, Vermont, attached in Appendix F.

Worms can also be used to engage children in learning about soils, biology, and gardening. It also provides an avenue for people without a lot of space to become involved in an agricultural activity (and reduce their waste). Summary Composting would build desert soil naturally lacking in organic matter. The cultivation of desert-adapted crops are recommended to increase Ajo’s food production without increasing artificial inputs.

Vermicomposting raised beds Photo Credit: Wikimedia commons

Worm Composting Vermicomposting (composting with worms) can process organic waste, and can be done on a small scale at home, in schools, or in restaurants. In apartments or places lacking in space, something as simple as a five-gallon bucket can be used to house worms. As with other types of composting, maintaining the proper aeration and moisture level prevents odors. Materials high in carbon are required for worm bedding: shredded newspaper, cardboard or straw work well. Making sure the worms are kept out of the hot sun is another important consideration in caring for worms—especially important in the desert.

A Sonoran Oasis soil & Vegetation


Land Availability Land ownership boundaries restrict the locations available for agriculture on the lands surrounding Ajo. Land can be divided up into three distinct categories of management, representing different opportunities for agricultural development.

County owns several plots just north of town, run by their Natural Resources Parks & Recreation (NRPR) department, and the Arizona State Trust owns several scattered plots south of Ajo around the town of Why. Privately owned lands make up the rest.

Land ownership The federally owned Barry M. Goldwater Range, the Cabeza Prieta National Wildlife Refuge, the Organ Pipe Cactus National Monument, the Tohono O’odham Nation, and lands managed by the Bureau of Land Management (BLM) completely surround Ajo, restricting agricultural production outside of town.

Unsuitable for Agricultural Production

Within Ajo, lands are divided between several landowner and manager categories. Pima

Land ownership and potential availability around Ajo


A Sonoran Oasis Land Availability

Cabeza Prieta National Wildlife Refuge Cabeza Prieta National Wildlife Refuge’s (NWR) 860,010 acres makes it the third largest national wildlife refuge in the lower forty-eight states. The refuge’s harsh and magnificent landscape of rugged mountain ranges and barren valleys is home to at least 391 plant species and more than 300 kinds of wildlife, including the

Roads Fragment Wildlife Habitat

Highway 86 cuts through the desert between Ajo and Tucson.

endangered Sonoran pronghorn and lesser long-nosed bats. Cabeza Prieta NWR is federally protected, designated by the United States Geological Survey (USGS) as GAP Status 1, meaning no development of any kind may happen there. The lands are being preserved for biodiversity management, ecological integrity, and wildlife habitat, and are not available for agricultural production in any manner.

Roads are an important factor in considering the Sonoran Desert Conservation Plan’s (SDCP) goals for county-wide riparian restoration, wateruse conservation, and priority species habitat protection. The SDCP guides “regional efforts to conserve the best lands and most precious resources for future generations of Pima County residents to enjoy.” The plan includes short-term actions and long-range land-use planning, and seeks to honor the county’s diverse ethnic and cultural backgrounds, and its rich diversity of plant and animal life. Though the BLM and Arizona State Trust own large areas of land outside Ajo, just a small portion of that is currently accessible by roads. While roads are important access and transportation corridors for people, they can cause tremendous damage to the fragile Sonoran desert ecosystem. A report filed as part of the SDCP concludes that “roads are recognized by conservation biologists as a chief threat to many sensitive animals and to the general integrity of ecosystems” (2002). It further identifies roads as a primary cause for soil compaction, species endangerment, and habitat fragmentation—specifically, for the endangered Sonoran pronghorn. The U.S. Air Force website for the Barry M. Goldwater Range agrees, “The desert soils are so sensitive that a single vehicle driving off the road can create a track that will last for decades.” Agriculture on accessible lands that minimize or eliminate the need for new roads will help preserve important desert habitat.

Cabeza Prieta NWR’s rugged mountains lie to the west of Ajo.

A Sonoran Oasis Land Availability


Organ Pipe Cactus National Monument “Organ Pipe Cactus National Monument celebrates the life and landscape of the Sonoran Desert,” the National Park Service pamphlet about the monument begins. The Monument provides numerous recreational opportunities, while preserving the wilderness of the desert, and was recognized by the United Nations in 1976 as an International Biosphere Reserve, along with its neighbor in Mexico to the south, El Pinacate Biosphere Reserve. Like Cabeza Prieta, Organ Pipe Cactus is federally protected and not available for food production. Barry M. Goldwater Range The Barry M. Goldwater Range is currently managed by the U.S. Department of Defense as an active military base. Parts have become important habitat for the cactus ferruginous pygmy owl, and the endangered Sonoran pronghorn, whose territory extends into the range from neighboring Cabeza Prieta NWR. Bombing is currently limited to designated areas of the range, and may be redirected or delayed if pronghorn are detected within five kilometers of the practice targets (Luke Air Force Base 2011). “There are literally thousands of square miles of undisturbed wilderness,” says the U.S. Air Force website about the range. The range is also not available for agricultural production in any manner.

Potentially Suitable as an Agricultural Partner: Tohono O’odham Nation It is beyond the scope of this assessment to recommend specific agricultural practices or land uses on the Tohono O’odham Nation. It is unknown if some tribal lands might be available for lease.


A Sonoran Oasis Land Availability

ISDA has partnered with O’odham elders on saguaro fruit harvests. Photo Credit: Jewel Clearwater

Suitable for Agricultural Purposes:

Lands owned by the Bureau of Land Management (BLM); Arizona State Trust; Pima County Natural Resources, Parks & Recreation; and privately owned parcels comprise the land ownership types most likely to be available for food production in the Ajo region. They have the potential to be bought or leased for growing food.

Developing Regional Partnerships

It is important to recognize the Tohono O’odham Nation as a potential partner and source of locally grown foods. Until the 1920s, the Tohono O’odham Nation used traditional farming methods to cultivate over 20,000 acres in the Sonoran Desert floodplains (TOCA 2010). But, “by 2000, that number was certainly less than 10” (TOCA 2010, 9).

locally-grown and regionally wild-harvested foods as possible. These foods provide a source of healthy, delicious foods that are especially beneficial for diabetics in regulating blood sugar levels: mesquite, chia, cholla buds, prickly pear fruit and pads, chiltepin, agave, organ pipe cactus fruit, and saguaro cactus fruit. The International Sonoran Desert Alliance (ISDA) has already collaborated with O’odham elders on traditional wild-harvests. Desert Rain Cafe and Indian Oasis/ Baboquivari Unified School District have negotiated with national food service distributor, SODEXO, to serve a traditional meal once a week. The school prepares the meal under direction of Desert Rain Cafe’s General Manager, Sam Saunders, who noted that the kids love the meal, “It’s a hit,” he said.

Anthony Francisco at Cowlic Farm on the Tohono O’odham Nation

In spite of this decline, the Nation now raises crops commercially on San Xavier Co-op, an 800-acre organic farm growing a variety of beans, corns, squashes, and more. Further efforts being undertaken by Tohono O’odham Community Action (TOCA) have resulted in the establishment of Papago Farms, Cowlic Farm and the Desert Rain Cafe, which features at least one traditional, desert-grown crop in each dish. “We’re just going back to the basics, back to traditional foods” TOCA Co-Director Terrol Dew Johnson told us, then added (referring to one report author), “I saw him scarfing down the cholla bud salsa—you can only buy that here!” Desert Rain tries to purchase as many

Tepary bean hummus and cholla bud salsa at the Desert Rain Cafe

These initiatives are positive models that can be adapted in Ajo. Continuing to build these relationships would increase the knowledge of edible desert plants and help maintain cultural practices.

A Sonoran Oasis Land Availability


Bureau of Land Management The BLM has a policy of leasing out lands to public interests for a variety of purposes. According to their Lower Sonoran Desert Field Office, “agriculture” refers only to cultivation of row crops; “grazing” refers to the production of cattle. The office has stated they have no formal policy against leasing land for agricultural use, though they also have no history of it in the area. In the past, nearly all lease requests have been for grazing, mining, or recreational use, not The sun sets over protected lands of the Sonoran Desert. for agriculture. Despite this, the BLM has recognized that the only desert land entry to reclaim, irrigate, and restrictions on agriculture are the same ones cultivate land which could not produce placed on other uses and requests. The land agricultural crops without the introduction and use must be recognized as falling within their application of water. habitat and wildlife species preservation requirements, which differ based on existing qualities of the land. Conversations with BLM The main hindrance to the modern applicability staff have indicated that the only identified of this act, and the reason Arizona and several priority conservation lands around Ajo are the other states currently have no land identified as Batamote Mountains northeast of town, and qualified for the Desert Land Entry Act, is lack of the Cuerda Delena Mountains southwest of water availability and cost. However, if a reliable town. water source were available that did not diminish or further stress the aquifer, the BLM lands could apparently be agriculturally The latest version of BLM’s Resource developed in accordance with the act. For more Management Plan for the Lower Sonoran Field about the Desert Land Entry Act and the Office is to be published in early April 2011, for application process, see Appendix C. public review. As BLM continues to examine their policies, it is hoped that they consider supporting sustainable agriculture projects in the region. The Desert Land Entry Act, passed by Congress in 1877, encourages and promotes the economic development of the arid and semiarid public lands of the western U.S., including Arizona. The act provides a path for an individual or group of individuals to apply for a


A Sonoran Oasis Land Availability

Planning for Endangered Species

For projects on federal land, a site-specific analysis must be conducted to determine if there will be an adverse impact or “take” on federally listed threatened or endangered species, or species of concern. The definition of take includes, but is not limited to, harassing or causing death, reproductive failure, or harm to wildlife. If it is determined that there is the potential of a take occurring, then the U.S. Fish and Wildlife Service (FWS) will review the project in accordance with section seven of the Endangered Species Act. The FWS will then determine the terms and conditions of a plan to minimize impacts of the proposed activity on endangered species. Under this assessment, federal lands, like the BLM parcel under consideration for agriculture in Ajo, are held to a higher standard than private land. On non-federal land, unless take is a possible consequence, activities are not restricted or subject to review. Residential sites are unlikely to warrant concern and will only be assessed if a clear case of possible take is self-reported. Therefore, the average home garden would be not be subjected to a formal review. The Arizona Fish and Game Department provides an online Environmental Review feature under Arizona Natural Heritage Programs, in which an area for a proposed project can be selected, generating a list of species of concern and endangered species present within a certain radius. A receipt will be produced indicating which agency must be contacted and what steps must be taken in order to proceed. Advice on methods for mitigating impacts is also provided. State Trust lands are also subject to this process.

Agricultural activity has the potential to affect endangered species and disrupt ecosystems. Understanding the implications of land use decisions can prevent unintended or unnecessary impacts such as the destruction of certain vegetation types. Because minimizing or mitigating damage to endangered species and species of concern is the goal of the FSW conservation plan, any proposed activity that accommodates habitat conservation will be assessed more favorably. When planning for food production, environmental and legal consequences can be avoided by planning for wildlife. Understanding the habitat requirements of species likely to be found on site can help one assess any proposed actions. Native plants, water, and areas for nesting and denning are components in beneficial habitat that may be simple to provide or avoid removing. Planting diverse polycultures that incorporate native plants in a variety of vegetation layers—and refraining from the use of chemicals—are ways to promote habitat health and produce food for people.

According to the National Park Service, in 2002 there were just twenty-five wild Sonoran Pronghorn left in Arizona. Photo Credit: USDA National Resources Conservation Service

A Sonoran Oasis Land Availability


To Ajo

High way 85



The Arizona State Trust parcel in Why is currently unleased.

Arizona State Trust The Arizona State Trust’s mission is to own and manage lands to “enhance value and optimize economic return for the Trust beneficiaries, consistent with sound stewardship, conservation, and business management principles.” The Trust provides support for resource conservation for the well-being of the public and the state’s natural environment. To that end, the Trust leases and sells parcels of land to interested parties, provided the proposed use is consistent with the mission of the State Trust. There are three Trust parcels about eleven miles south of Ajo in the small community of Why. Only one of the three parcels, covering 640-acres located between State Routes 85 and 86, is currently unleased, but its well is dry.


A Sonoran Oasis Land Availability

gh wa y8


Eric Marcus Municipal Airport

Ajo W ell Rd

. No. 1

To Highway 85

Ajo Regional Park, managed by the Pima County Natural Resources, Parks & Recreation

Pima County Natural Resources, Parks & Recreation Pima County Natural Resources, Parks & Recreation’s (NRPR) mission is “to conserve the Sonoran Desert and enhance the urban environment while providing quality recreational, educational, and leisure activities.” Within that vision, the department runs a variety of parks throughout Pima County, including dog parks, pools, shooting ranges, recreational trails and more. Currently, an area of Ajo Regional Park, run by Pima County NRPR, has been leased to the nonprofit Why-AjoLukeville Development (WALD) group to run rodeo and roping grounds. If other lands are available for lease, members of the ARFP may be ideal candidates to help manage the land by integrating educational and recreational opportunities with agricultural production.

A Sonoran Oasis Land Availability


No. 1 Ajo W ell Rd .

Cabeza Prieta National Wildlife Refuge


High way 85

Ajo zoning map

Private Lands Pima County zoning regulations do not permit certain agricultural activities on privately owned lands. As the chart on the next page shows, much of Ajo’s zoning allows for agricultural production, but restricts crops grown in many zoning types from being sold commercially. Currently, only crops grown in suburban homestead (SH) zone, which makes up most of the northern section of town along the highway 85 corridor, may be sold commercially. As Pima County continues to revise zoning regulations, recent interest in urban farming in Ajo, Tucson, and the rest of the country should be taken into consideration. Removing current restrictions on crop retail sales is recommended, which would allow residents to legally sell their produce to neighbors, or at a farmers market. 46

A Sonoran Oasis Land Availability

Aerial photo analysis (see pages 49 and 50) shows approximately 271 acres of privately held open space available in town in back and front yards, and in undeveloped lots. (These calculations excluded roads, and public and commercial spaces. For more about the calculation of this space, see Appendix C.) Also, land on either side of Ajo’s over 50 miles of roads is held in public ownership as a right-of-way. The Pima County policy for planting in the road rights-of-way, is designed to “assist in furthering the community goal of increasing vegetative cover with the associate benefits” (Policy F 54.1, 1). Herbaceous plants should not be grown for consumption in this right-of-way zone due to the potential for contamination from

Zone Type





Local and  general  business

Not Specified

GR 1  -­‐  Rural  Residen;al

"...encourage orderly  growth  in  rural  and   semirural  areas  as  well  as  to  provide   opportuni;es  for  semirural  residen;al   uses...intended  to  allow  commercial   development  only  where  appropriate   and  necessary..."


Crops may  not  be  grown   for  retail  sale;  Raising  of   poultry  or  other  small   animals  allowed,  provided   there  are  no  more  than   forty  animals  per  acre

Light Residen;al

Single Residence/  Mixed  Dwelling


Crops may  not  be  grown   for  retail  sale

RH -­‐  Rural  Homestead

" preserve  the  character  and   encourage  the  orderly  growth  of  rural   areas  in  the  encourage  rural   development  in  areas  lacking  facili;es  for   urban  development  and  to  provide  for   commercial  and  industrial  development   only  where  appropriate  and  necessary..."


Crops may  not  be  grown   for  retail  sale

SH -­‐  Suburban  Homestead

"...a low  density  zone  principally  for   single-­‐family  residences  and  associated   condi;onal  uses  on  large  lots.  A  wide   range  of  agricultural  and  ranch  uses  are   permi<ed."


Farm stand  may  only  sell   products  grown  or   produced  on  the  premises


Industry; limited  retail

Not Specified

IR -­‐  Ins;tu;onal  Reserve

"...federal, state,  city,  county,  Indian  and   other  publicly  owned  lands.  It  is  intended   that  these  lands  remain  as  a  reserve  un;l   such  ;me  they  are  released  to  the   private  sector."


TR -­‐  Transi;onal  Zone

Residen;al; office;  motel/hotel;  day  care;   health  care  center;  etc.


TH &  CMH  -­‐  Trailer  and   Camper  Homesites

Travel trailers,  motor  homes,  and   campers  

Not Specified

Crops may  not  be  grown   for  retail  sale

Note: Arizona  state  law  specifies  no  zoning  regula4ons  may  be  placed  on  agricultural  ac4vi4es,                        including  compos4ng,  occurring  on  a  tract  of  land  that  is  five  or  more  con4guous  commercial  acres  .

Ajo zones and their possibilities for agricultural production

A Sonoran Oasis Land Availability


road run-off. However, toxins are less likely to accumulate in the edible portions of woody plants. Pima County’s list of approved trees for planting in the right-of-way includes several trees with edible fruits or beans, though the county may be amenable to the suggestion of including other species. Approved edible trees are mesquite (velvet & screwbean); palo verde (blue & foothills); pomegranate; and acacia. Planting in privately held open spaces and the public rights-of-way might enable Ajo to realize new opportunities for food production.

Tucson’s Youth Mapping and Gleaning Project, began by a group of teens in 2003, aims to redistribute food already being grown in town that would otherwise go to waste. Their first harvest collected around 1000 pounds of produce, herbs, and eggs from Tucson’s public and private fruit trees. The day’s bounty was given away free in Jefferson Park and to charities like the Southern Arizona AIDS Foundation. Thus far, the mapping project has identified 296 fruit trees on 162 individual properties throughout Tucson.

Ajo’s streetscape above can be enhanced by right-ofway trees. Photo Credit: Google Maps

Gleaning & Public Spaces: An Edible Streetscape There is a growing national movement of people reviving the ancient practice of gleaning, harvesting fruit that would otherwise go to waste. Gleaning groups have formed in many urban locations and websites like list over 10,000 public fruit trees across the country.


A Sonoran Oasis Land Availability

Gleaned figs in Australia are free for the taking. Photo Credit: donkeycart

Potentially Available Open Space in Ajo Rights-of-way on Ajoâ&#x20AC;&#x2122;s road have the potential for edible streetscapes.

Empty lots can be converted into neighborhood gardens.

Privately owned yard space may contribute to food production.

Over fifty miles of rights-of-way and 271 acres of open space in town are potentially available for food production.

A Sonoran Oasis Land Availability


Ajoâ&#x20AC;&#x2122;s dense and less-dense areas have an estimated 116 acres and 155 acres of open space, respectively. For more detail about the calculation of this space, see Appendix C.


A Sonoran Oasis Land Availability

Community Grown Food Case Study: NeighborSpace

Since 1996, the nonprofit NeighborSpace has been working across Chicago to help community groups acquire vacant lots, parks, gardens, and other open spaces for conservation, community food production, educational programs, beautification projects, and more. NeighborSpace works on developing partnerships with local residents, businesses, private organizations, and public agencies to ensure long-term success. As a community land trust (CLT), NeighborSpace maintains ownership of the land even if occupants change. Thus, long-term investments, like the addition of fruit trees, may be made. NeighborSpace currently owns fifty-seven sites and holds long-term leases for four more. Another twenty sites are involved in the review or acquisition process. These projects have helped NeighborSpace win numerous awards, including the Award for Excellence in Resource Management from the International Council for Local Environmental Initiatives in 2000. A CLT following the model of Chicago’s NeighborSpace could help make it easier to grow food on all available spaces by reducing land ownership and liability costs for groups and nonprofits. A CLT could require that renovated and new homes on their properties capture rainwater runoff to grow edible native vegetation. A CLT could also manage seasonal residents’ properties by taking responsibility for fruit trees and other edible landscaping.

Attempts are underway to institute a gleaning program in Ajo. Though still small in scale, organizers are hoping to enlist more seasonal residents to donate their fruit in exchange for tree maintenance. Harvests have been donated to the food bank. Trees that produce fruit, nuts, and edible pods growing in Ajo’s public spaces could contribute to the town’s food supply. Community Land Trusts A community land trust (CLT) might provide a way of acquiring vacant lots and empty homes in Ajo as a part of a larger plan to increase food production. A CLT is a nonprofit organization that purchases and then leases out properties to an individual homeowner, community development organization, or some other nonprofit. A CLT may permit certain uses for the property, or place certain conservation conditions or restrictions on the land. CLTs also ensure that a piece of land is used for a community-identified purpose, like affordable housing, commercial enterprises, or increasingly, agricultural production. The governing structure of a CLT is typically organized to include an entire community’s interests. Summary The limited space available for food production in Ajo is challenging, but does not mean that food production cannot happen. Public rightsof-way, backyards, and empty lots could provide space for increased food production in town, while potentially available land out of town could provide space for larger scale cultivation.

A CLT is a long-term investment in the future of Ajo that enables everyone in the town, regardless of income or gardening ability, to have access to fresh fruit.

A Sonoran Oasis Land Availability


Vision: Ajoasis AjOasis In this future vision for Ajo, the unique flora and fauna of the Sonoran Desert coexist with a productive landscape, creating an oasis in harmony with ecological and hydrological processes: AjOasis. AjOasis is a vision whereby the carrying capacity of the desert determines the limits to agriculture, and crops and farming techniques adapted to the Sonoran Desert are used to maximize food production. The resilience inherent in diverse ecosystems can be used as a model for developing effective management strategies for food production. In an increasingly unpredictable environment, a variety of approaches to production offers the most stability and food security. AjOasis has two major production areas: in town and just out of town.

Food Production in Town The estimated 271 acres of private, undeveloped land and the fifty miles of roads, represent a significant opportunity to expand efforts to develop a local food system in the midst of Ajo. Underutilized spaces in backyards, empty lots, and rights-of-way are planted with a variety of crops and useful native plants, for example, mesquite, citrus, and pomegranates. Plants requiring the greatest level of care are grown close to houses, taking advantage of rooftop runoffâ&#x20AC;&#x201D;while household greywater is reused on fruit trees. Neighborhood composting and vermicomposting transform organic household wastes into a valuable amendment that is used to enrich poor soils. An emphasis on raising desert-adapted strains of familiar vegetables like melons, squashes, and salad greens allows for greater water conservation and overall success. Residents have developed a strong partnership with the Tucson-based Native Seeds/SEARCH, an organization that works to conserve the genetic heritage of regional crops, and from which they obtain seeds.

A vision of a street in Ajo where water harvesting techniques help residents to grow food in yards and in public rights-of-way.


A Sonoran Oasis Vision: Ajoasis

A cross section of potential home, neighborhood, and community scales of food production in Ajo.



A community land trust (CLT) enables groups to turn vacant lots into neighborhood centers through which resources, expenses, knowledge, and responsibilities are shared. Shared equipment, like tillers and garden tools, reduce costs by dividing their expense among the growers. Greenhouses on CLT land extend the growing season and aquaponics systems grow tilapia and common vegetables, like tomatoes, peppers and salad greens. Communally raised bees and chickens allow people to maintain some flexibility in their schedules, while still enjoying the benefits of fresh honey, eggs, and meat. Stormwater harvested from bordering roads is used to moisten the compost being created and to water fruit trees. The varied food produced here may be eaten by residents or sold at the local farmers’ market. The CLT lots compost more organic material than at a typical residence and with greater efficiency, allowing those who choose not to compost at home to still support food production. With multiple spaces larger than typical single-family lots, more of the regionally available manure can be composted. Worms from vermicomposting cycle back into the system by feeding chickens and aquaponic fish.


Public Right-of-Way Orchard Street-side orchards of trees like hackberry, olives, and pomegranates, and shrubs like wolfberry, are interplanted with nitrogen-fixing ironwood and mesquite trees, which provide soil nutrients, shade, food, and habitat for pollinators. Following the lead of other arid communities like Phoenix, young trees are established using “tall pot technology” (page 38) and time-released water capsules to make certain the trees have adequate water to get established. Curb-cuts and check dams channel stormwater from streets through mulched swales to help sustain trees. By removing unnecessary pavement (which can be recycled) water can penetrate into the soil, where it becomes accessible to plant roots. Like Brad Lancaster’s street in Tucson and Seattle’s SEA Street, a high-profile location in Ajo has been chosen to initially demonstrate the potential for re-planting the typical roadway. The current gleaning program harvests from these roadside areas. The collected food is donated to the food bank or eaten by gleaners.

A Sonoran Oasis Vision: AjoAsis


A farm outside town can reuse wastewater to create a desert oasis.

Wastewater treatment

Purification wetlands

At the School Building on the momentum and enthusiasm for the gardening project already underway at the Ajo Unified School District, students participate in a range of activities related to food production. By studying O’odham history and ak-chin farming techniques, students learn about sustainable living in the desert environment, while gaining an appreciation for native culture. School-wide vermicomposting of food scraps and waste paper build soils for school gardens, supporting student run microenterprises selling foods they have grown or value-added products they have made, while gaining practical skills in business. Through gardening, gleaning, raising fish, and wildharvesting plants, students produce their own healthy foods for the school, while increasing their interest in learning about and eating these foods.

Polyculture Orchard

Educational Oasis

Ajo Regional Park

BLM Land

The farm stand at the Curley School becomes Wastewater a farmer’s market and meeting place where Treatment people sell and trade their extra produce. Value-added items are processed at commercial kitchens, like the one started by Ajo Cooks! at the Curley School, and kitchens rented from town restaurants. Acceptance of food coupons from the Women, Infants, and Children program (WIC), Commodity Supplemental Food Program (CSFP) for seniors, and the Arizona Farmers Market Potential future path of wastewater through BLM lands and Nutrition Program enhance the market’s towards Ajo Regional Park accessibility to all income levels. 54

A sonoran Oasis Vision: Ajoasis

The farm outside town can support different growing and harvesting styles, from orderly field crops to wild harvests.

Field Crops

Polyculture Orchard

Growing food on larger properties out of town Locations on the periphery of Ajo have been transformed into hubs of agricultural activity by reusing the over forty-six million gallons of wastewater generated annually in Ajo. Commercial Farm From the treatment wetlands adjacent to the wastewater facility, water flows to a commercial farm on a 320-acre tract of BLM land next to the eastern border of Ajo Regional Park. The property is chosen because of its prime soils, and acquired through the Desert Lands Entry Act (as described in detail in Appendix C). Canals control irrigation on the farm, which grows crops for residents and developing markets.

Wild Harvest

Managing this diverse and productive ecosystem creates food-related jobs, both on-site and off. Teaming up with the Ajo Cooks! program, entrepreneurs turn raw produce into value-added products such as pomegranate juice and mesquite flour, which have found growing niche markets. Some of the produce and value-added products are also sold at local retailers, like Olsenâ&#x20AC;&#x2122;s IGA market. The health benefits of mesquite pods, flour, and other foods with a low glycemic-index are promoted for use by diabetics. A variety of distribution channels, like a cooperative grocery or a Community Support Agriculture program, provide affordable and accessible food for residents.

A pomegranate and mesquite tree overstory is interplanted with an understory of perennial crops like nopales, buckthorn cholla, and others, while a live ocotillo fence deters javelina and rabbits from browsing. Desert-adapted annuals, like chia and amaranth, are combined with heritage varieties of familiar foods, like corn, squash, melons, and beans. By sowing diverse grains, legumes, and vegetables at intervals, harvests are staggered and food is always available. Bees pollinate the crops while producing prized mesquite honey.

A Sonoran Oasis Vision: AjoAsis



Education, Traditional Farming, & Wild Harvest An educational working farm could serve as an educational site for students, residents, and visitors. A partnership with Why-Ajo-LukevilleDevelopment (WALD) creates compost from the manure produced on their rodeo and roping grounds.

On the lagoonâ&#x20AC;&#x2122;s periphery, native edible plants are harvested from a mesquite bosque. This type of mesquite forest, which once covered large swaths of Sonoran Desert, creates microclimates and habitat for rare and endangered species, and opportunities for hiking, learning about regional ecology, edible wild plants and ak-chin farming.

Water not used for irrigation on the commercial farm flows through a canal into the Ajo Regional Park operated by Pima County, where it collects in a lagoon. Intentional leaks in the canal help support riparian habitat, compatible with the goals of the Sonoran Desert Conservation Plan. The lagoon, just several feet deep, provides wildlife, like migratory birds and the endangered Sonoran pronghorn, access to drinking water and the cover of wetland vegetation.

By increasing habitat for native species and adapting ancient farming methods, Ajo has become more than just a stopover point for tourists and passersby taking Highway 85 to Mexico, Organ Pipe National Monument, or the Tohono Oâ&#x20AC;&#x2122;odham Nation. Visitors are drawn by opportunities to view rare wildlife, eat traditional native foods and other regional fare, learn about ak-chin farming, and visit the historic revitalized downtown.

A sonoran Oasis Vision: Ajoasis

Water-harvesting, food-producing streetscape in Tucson.

Summary The reality of living in Ajo’s extremely arid environment is that some use of aquifer water may be necessary to grow food, even if it is still unclear whether withdrawing water will be sustainable. Minimizing water use with techniques described in the vision for AjOasis will help reduce financial and environmental impacts and allow for food production in unlikely places. Reuse of wastewater in particular represents a tremendous opportunity.

thousands of miles away. By transforming this linear model into a circular one, resources can be shared among organizations; one group’s waste literally becomes another’s nutrients—be it manure and food scraps into compost, or waste water into irrigation. Sharing resources and bringing people into a greater sense of community can help Ajo become an AjOasis.

Ajo’s one-way resource use, whereby goods imported to town or extracted from the ground are used and then disposed of, is unsustainable and has left Ajo vulnerable to markets

A Sonoran Oasis Vision: AjoAsis


Works Cited Ajo Copper News, March 19, 2008, Arizona Department of Water Resources (A): “Sharing Arizona’s Water Future: Gila Bend Basin,” Accessed March 20, 2011, OutsideAMAs_PDFs_for_web/Lower_Colorado_River_Planning_Area/Gila_Bend_Basin.pdf Arizona Department of Water Resources (B): WaterAtlas/LowerColoradoRiver/Groundwater/LowerGila.htm Arizona Department of Water Resources, Lower Colorado River Hydrology -Groundwater (West Basins) PlanningAreaOverview/HydrologyWest.htm#Butler. (C) Updated: November 18, 2010 Arizona Department of Water Resources, Phone Conversation: Water Rights (D) Arriaga et al., 1993. “Association Between Cacti and Nurse Perennials in a Heterogeneous Tropical Dry Forest in Northwestern Mexico.” Journal of Vegetation Science 4 (1993):349-356. “Australia Floods: Food Prices to Rise 30%,” BBC News, January 11, 2011, news/business-12162952 Bashan et al., “Prevention of Desert Soil Erosion and Enhancing Soil Stabilization by Mychorrhizal Fungi and Cactus Plants Innoculated With Azospirillium Brasilense,” The Center for Biological Research of the Northwest (CIB), La Paz, Mexico, 2005 Bechtol, Vanessa, Local & Heritage Foods Directory: A Guide to Producers, Grocers, Restaurants and Farmers’ Markets Throughout the Santa Cruz Valley and Southeastern Arizona, Santa Cruz Valley Heritage Alliance, June, 2009. “Boundary Descriptions and Names of Regions, Subregions, Accounting Units and Cataloging Units, U.S. Department of the Interior,” U.S. Geological Survey, html#Region15. Updated: July 29, 2010. Burros, Miriam, “Obamas to Plant Vegetable Garden at White House,” New York Times, March 19, 2009, “Cabeza Prieta National Wildlife Refuge.” Accessed March 2011, refuges/arizona/cabeza/index.html


A Sonoran Oasis Works Cited

Canning, Patrick, “A Revised and Expanded Food Dollar Series: A Better Understanding of Our Food Costs” USDA Economic Research Report Number 114, February 2011 CAP, Central Arizona Project.: Diver, Steve, “Aquaponics-Integration of Hydroponics with Aquaculture,” National Sustainable Information Source, Published 2006. Updated 2010. Doolittle, William E., Cultivated Landscapes of Native North America. New York: Oxford, 2000 Elder, Miriam, “Russia: Fire Scorches Wheat Crop,” Global Post, August 16, 2010, http://www. Fish, Suzanne, “Hohokam Agave Cultivation,” Southwest Agave Project, http://www.ic.arizona. edu/~agave/hohok_agave01.htm. Updated: July 28, 2004. Fulton, April, “Most Americans Worry About Food Supply,” National Public Radio, July 27, 2010, most-americans-worry-about-safety-of-food-supply “Geologic Provinces in the United States: Basin and Range Province,” Accessed March 2011, http:// “Ground Water Atlas of the United States: Arizona, Colorado, New Mexico, Utah, USGS HA730,” Gulyas, H., “Resource Management Sanitation, Lession B1,” Institute of Wastewater Management, Hamburg University of Technology, Germany, 2002 Hewitt, Ben, The Town That Food Saved. New York: Rodale, 2009 “Hot Fire, Weather in Russia Boom Wheat Prices,” Associated Press, August 3, 2010, http://www. Hurt, Douglas R., Indian Agriculture in America. Lawrence, Kansas: University Press of Kansas, 1987 “Investigation Update: Outbreak of Salmonella Typhimurium Infections 2008-2009,” The Center for Disease Control, April 29, 2009,

A Sonoran Oasis Works Cited


Johnson, William, “Soil Survey Area: Gila Bend-Ajo Area, Arizona, Parts of Maricopa and Pima Counties,” National Resource Conservation Services. Version 8. September 2, 2008 Jones, Lynn, “Economic Advantages of Local Food,” Ottawa River Institute, August 30, 2010. Accessed March 13, 2011. watershed-ways/65-2010/614-economic-advantages-of-local-food “Keystone Species Fact Sheet,” Sonoran Desert Conservation Plan, 2006, Accessed March 2011, Lancaster, Brad, Rainwater Harvesting for Drylands and Beyond: Volume 2. Tucson, Arizona: Rainsource Press, 2008 Larry Onyskow, phone conversation, March 2011 Lechner et al, “Tall Pot Technology: Establishing Vegetation in Harsh Climates,” Land and Water Magazine, January/February 2011, 35 Legere, Richard H., “Ecosystem Restoration in the Sonoran Desert” U.S. Army Corps of Engineers, Water Resources Planning, Accessed March 20, 2011, PlanningCOP/Documents/plan_conf/2010/Presentations/ses3_1d.pdf. Licamele, Jason D., “Sustainable Integrated Farming,” Accessed March, 18, 2010, http://www. “Links to Our Past: Ghost Town and Mining Town of Pima County,” Pima County, AZ Staff, September 2001, “Low tech, high impact,” Michigan Tech Engineering, Undergraduate Education: Beyond the Classroom, 2010, Lower Colorado River Hydrology-(Groundwater West Basins),Arizona Department of Water Resources, PlanningAreaOverview/HydrologyWest.htm. Updated November 18, 2010 Lowry, Jr., J.H. et al, “Land Cover Classification and Mapping” in J.S. Prior-Magee, et al., eds. Southwest Regional Gap Analysis Final Report, U.S. Geological Survey, Gap Analysis Program, Moscow, ID, 2007


A sonoran Oasis Works Cited

“Luke Air Force Base,” Accessed March 2011. Nabhan, Gary, Enduring Seeds: Native American Agriculture and Wild Plant Conservation. New York: North Point Press, 1995 Nabhan, Gary, The Desert Smells Like Rain, Tucson: University of Arizona, 2002 Nabhan, Gary, and Regina Fitzsimmons, eds. “State of Southwestern Foodsheds: A Special Publication of Sabores Sin Fronteras,” the Southwest Center with Edible Communities, 2011. Nabhan et al. “Papago Influences on Habitat and Biotic Diversity: Quitovac Oasis Ethnoecology” Journal of Ethnobiology, Vol.2, No. 2, 1982, 124-143 “Neighborhood Fruit”, Accessed March 18, 2011 Nobel, P.S., “Effect of Nurse Plants on the Microhabitat and Growth of Cacti,” Journal of Ecology British Ecological Society, Vol. 77, No. 3 pp. 870-886 1989 Pima County, “Brownfields Grant Application for Fiscal Year 2010: Community-Wide Assessment Grant-Petroleum Products and Hazardous Susbstances,” October 15, 2009 Pima County, “Sonoran Desert Conservation Plan, Riparian Protection and Restoration Element: Adopted Goal Statements,” April 24, 2000, HTM Pollan, Michael, The Omnivore’s Dilemma: A Natural History of Four Meals. New York: Penguin, 2006. Pothukuchi, Kami, Hugh Joseph, Hannah Burton, and Andy Fisher, What’s Cooking in Your Food System: A Guide to Community Food Assessment, Community Food Security Coalition, 2002 “Pulling Fresh Fish Out of the Sonoran Desert,” Inside Tucson Business, December 4, 2009, http://

A Sonoran Oasis Works Cited


Purcell, Denise, “SIAL 2010: 15 Trends That Will Shape Tomorrow’s Food Products,” Specialty Foods Magazine, Accessed March 18, 2011, Reza Zolfaghari, “Nutritional evaluation of honey mesquite pod and seed (Prosopis glandulosa)” Texas Tech University, 1984 Robbins, John, The Food Revolution: How Your Diet Can Help Save Your Health and Our World. San Francisco: Conari Press, 2001 Rogers, Lois, “Child Diabetes Blamed on Food Sweetener,” The Sunday Times, December 13, 2009, Accessed March 16, 2011, Severson, Kim, “Neighbor, Can You Spare a Plum?” The New York Times, June 9, 2009, Accessed March 18, 2011, Sheridan, Thomas E., Landscapes of Fraud: Mission Tumacácori, The Baca Float, and the Betrayal of the O’odham. Tucson: The University of Arizona Press, 2006 Spencer Musgrove, “Basin and Range Aquifers for Arizona” Introduction to Hydogeology, Spring 2005, hm Stute, Martin, “Lecture 8: North American Groundwater Issues,” Environmental Science for Decision Makers, Columbia University, Fall 2003, lectures/08. Suddath, Claire, “Brief History: Food Recalls,” Time Magazine, September 6, 2010, http://www.time. com/time/magazine/article/0,9171,2013825,00.html Tohono O’odham Community Action, “Community Context: The Tohono O’odham Nation,” http:// Oodham_Nation.html, Updated September 2009, Accessed March 2011. Tohono O’odham Community Action, From I’itoi’s Garden, 2010 USGS:1,


A sonoran Oasis Works Cited

Vandermeer, John, “Saguaros and Nurse Trees: A New Hypothesis to Account for Population Fluctuations” The Southwestern Naturalist, Vol. 25, No. 3 (Nov. 14, 1980), 357-360 “Water Resources of the United States,” United States Geological Survey, Accessed March 2011. “Western Regional Climate Center,” “Water Quality Forum, Riparian Areas: Regulatory Controls in Eastern Pima County,” Pima Association of Governments, January 9, 2003, RiparianForumReportMar03.pdf

A Sonoran Oasis Works Cited


Appendix A Arizona State Greywater Law R18-9-711. Type 1 Reclaimed Water General Permit for Gray Water A Type 1 Reclaimed Water General Permit allows private residential direct reuse of gray water for a flow of less than 400 gallons per day if all the following conditions are met: 1. Human contact with gray water and soil irrigated by gray water is avoided; 2. Gray water originating from the residence is used and contained within the property boundary for household gardening, composting, lawn watering, or landscape irrigation; 3. Surface application of gray water is not used for irrigation of food plants, except for citrus and nut trees; 4. The gray water does not contain hazardous chemicals derived from activities such as cleaning car parts, washing greasy or oily rags, or disposing of waste solutions from home photo labs or similar hobbyist or home occupational activities; 5. The application of gray water is managed to minimize standing water on the surface; 6. The gray water system is constructed so that if blockage, plugging, or backup of the system occurs, gray water can be directed into the sewage collection system or on-site wastewater treatment and disposal system, as applicable. The gray water system may include a means of filtration to reduce plugging and extend system lifetime; 7. Any gray water storage tank is covered to restrict access and to eliminate habitat for mosquitoes or other vectors; 8. The gray water system is sited outside of a floodway; 9. The gray water system is operated to maintain a minimum vertical separation distance of at least five feet from the point of gray water application to the top of the seasonally high groundwater table;


Ajo Food Assessment Appendix A

10. For residences using an on-site wastewater treatment facility for black water treatment and disposal, the use of a gray water system does not change the design, capacity, or reserve area requirements for the on-site wastewater treatment facility at the residence, and ensures that the facility can handle the combined blackwater and gray water flow if the gray water system fails or is not fully used; 11. Any pressure piping used in a gray water system that may be susceptible to cross connection with a potable water system clearly indicates that the piping does not carry potable water; 12. Gray water applied by surface irrigation does not contain water used to wash diapers or similarly soiled or infectious garments unless the gray water is disinfected before irrigation; and 13. Surface irrigation by gray water is only by flood or drip irrigation.

Brad Lancaster flood irrigates different fruit trees with his laundry machineâ&#x20AC;&#x2122;s greywater.

Appendix B Greywater It is estimated that a family of four uses 22,484 gallons of water per year in greywater from their washing machine, bathroom sink and shower, and kitchen sink. This could help support the water requirements for a 16ft citrus tree (7,250 gallons/year); a 20ft mesquite tree (2,940 gallons/yr); an 18ft apricot tree (4,293 gallons/yr); an 18ft hackberry tree (4,293 gallons/yr); and an 18ft olive tree (5,562 gallons/yr). Combined, these five fruit trees consume an estimated 24,338 gallons of water per year. The remaining 1,854 gallons could be captured by roof rainwater (Lancaster 2008, 308). Greywater Laundry System information, from the Watershed Management Group: files/docs/wmg_greywater_handout.pdf

Greywater Laundry System parts list, from the Watershed Management Group: files/docs/wmg_laundry_greywater_materials_ list.pdf Greywater Information, from Oasis Design: files/docs/azgwhandout.pdf Greywater Use Laws and Recommendations from the Arizona Department of Environmental Quality: download/graybro.pdf

An orange tree is grown with laundry greywater at Brad Lancasterâ&#x20AC;&#x2122;s Tucson home.

A Sonoran Oasis Appendix B


Appendix C GAP Status 1 GAP Status 1 indicates, “an area having permanent protection from conversion of natural land cover and a mandated management plan in operation to maintain a natural state.” More information about the USGS GAP Status designations can be found at Desert Land Entry Act The Desert Land Act of 1877 was enacted to encourage the reclamation or restoration (by cultivation and irrigation) of land, which could not produce agricultural crops without the introduction and application of water. The cultivation of native desert plants that are not dependant on percolating waters or irrigation does not qualify as a crop that meets the entry on public lands under the Desert Land Act. The Desert Land Act was amended on March 3, 1891 to require that applicants prepare a plan of proposed irrigation. The plan should have sufficient detail to show that the irrigation and reclamation of the land will lead to the success of raising ordinary agricultural crops. Raising crops without irrigation is not evidence of reclamation of the land, [see: United States v. Grancer D. Jenkins, 11 IBLA 18 (May 21, 1973)]. A 320-acre tract of land must be, according to the BLM, “surveyed, unreserved, unappropriated, non-mineral, non-timber, and incapable of producing an agricultural crop without irrigation.” Further, the lands must be more valuable for agriculture than any other purpose. If one successfully proves to the BLM that the required money is spent on improvements to reclaim, irrigate and cultivate the land for the first three years of the project, one receives the legal title to the lands from the BLM.


A Sonoran Oasis Appendix C

The BLM estimates that costs for setting up irrigation for a 320-acre tract of land would be roughly $250,000, an amount the BLM recognizes as a significant deterrence. An email exchange with the BLM conceded, “if you are considering grey water harvesting, in which you would only be using reclaimed or recycled water, as you described to me over the phone, this might justify the utilization of this Act” (March 11, 2011). Frequently Asked Questions about the Desert Land Entry Act on the BLM website can be found at: more/lands/desert_land_entries.html Information about the application process can be found at: title43/43cfr2920_main_02.html Laws pertaining to the Desert Lands Entry Act can be found at: cgi/t/text/text-idx?c=ecfr&tpl=/ecfrbrowse/ Title43/43cfr2520_main_02.tpl

Orthographic Photo Extrapolation This estimate was generated by sampling representative blocks for permeable surface area and extrapolating to the rest of the neighborhood. Five representative blocks in the densely developed urban section of Ajo have an average 0.8 acres of permeable surface per block. When multiplied by the 145 blocks of this development type, 116 acres are revealed as potentially available. Five representative blocks in the less dense suburban neighborhood to the north average 6.2 acres of permeable surface per block. When multiplied by 25 blocks of this development type, 155 acres are revealed as potentially available.

Appendix D Determining Agricultural Carrying Capacity Creating an accurate dietary-based model for determining the agricultural carrying capacity of Ajo requires further study. Such study should investigate: • Determining the diet of the population of Ajo, including overall consumption and food eaten • Determining land productivity for various methods of agriculture and livestock • Comparing diet to potential land productivity • Analyzing effects of dietary modification • Optimizing for food chain efficiencies and local sourcing Useful models and methodologies for creating such a study include: Christian J. Peters, Jennifer L. Wilkins and Gary W. Fick, “Testing a complete-diet model for estimating the land resource requirements of food consumption and agricultural carrying capacity: the New York state example.” Renewable Agriculture and Food Systems 22, No. 2, 2006: 145-153. Christian J. Peters, Nelson L. Bills, Arthur J. Lembo, Jennifer L. Wilkins, Gary W. Fick, “Mapping potential foodshed in New York State: A spatial model for evaluating the capacity to localize food production,” Renewable Agriculture and Food Systems 24, No. 1, 2008: 72-84.

a Sonoran Oasis Appendix d


Appendix E Crops According to Specialty Foods Magazine (2010), some national emerging food trends include exotic and locally produced foods. The desert’s delicious wild-harvested foods, expertly harvested by the Tohono O’odham, might generate income as specialty products.

Gu Achi Trading Post in Sells, Arizona, highlights its traditional foods.

Brad Lancaster’s Rainwater Harvesting for Drylands and Beyond, Volumes 1 and 2 is an excellent resource for specifics on planting designs, rainwater harvesting construction, and water use calculations. A plant list appendix from the book, full of information on plant uses, sizes and site requirements, is available on the web at: wp-content/uploads/Appendix4PlantLists.pdf Native Plant Polycultures “The line between domesticated and wild blurred in O’odham fields, where diversity was more valued than yield per unit of land” (Sheridan 2006, 37). “I remembered that for some of the Tepimanspeaking groups, such as the River Pima and Tohono O’odham, the words for ‘wildness’


A Sonoran Oasis Appendix E

(doajk), for ‘wholeness’ and for ‘health’ (doajig), appear to be etymologically related. These words are probably rooted in the term doa, ‘to be alive’ or ‘to be cured’” (Nabhan 1995, 32). A polyculture is the planting of multiple species within proximity to one another. If planned appropriately, the species within the polyculture will reduce competition by each filling a different niche. This method maximizes use of space by stacking crops in vertical layers. A canopy layer shades the ground below it, a shrub layer, an herbaceous layer, and vine layer. Similarly, the roots are not in direct competition as their different forms reach into different soil layers. This system is more resistant to pest species, since they are not drawn by a uniform food source. By supporting biodiversity, this system also attracts natural predators that keep pest damage to a minimum (Wikipedia 2010). The following crops are just a selection of the multitudes of available desert-adapted crops that can be planted in a polyculture. We encourage having fun choosing new plants and trying new foods: Tepary Beans This healthful bean, domesticated by the ancestors of the Tohono O’odham, has been called “the little power-packed bean” that “kept them [the Tohono O’odham] full of sustained energy, healthy, and able to run long distances...” (Bechtol 2009). The tepary bean has more protein and complex carbohydrates than any common bean, and is reportedly much better at regulating blood sugar for diabetics. As a desert-adapted crop, it is highly adapted to the hottest desert temperatures and the extremes of the monsoon rains (Bechtol 2009). An unirrigated crop of tepary beans is said to yield 450 to 700 pounds per acre, while an irrigated crop will yield as much as 800 to 1500 pounds per acre (Hurt 1987).

Chiltepin Known as “the mother of all chiles,” chiltepines grow on rocky, steep slopes, underneath shrubs, making harvest difficult. In Sonora, Mexico, whole communities wild-harvest the chiltepin each fall. “Prices can reach upwards of $72 per pound”(Bechtol 2009). Cholla Since the buckthorn and staghorn cholla were the first vegetables available in early spring, they were highly valued by the Tohono O’odham. Cholla buds have been “an important, high quality, low calorie food source for generations” (Bechtol 2009). Just two tablespoons of dried buckthorn cholla contain as much calcium as a glass of milk, with just a fraction of the calories (TOCA 2010).

northwestern Mexico. Even in the inhospitable climate of Death Valley, California, the staple food was the mesquite bean.” Mesquite flour is effective in stabilizing blood sugar level in diabetics and the pods are a good source of protein, calcium, iron, and other nutrients (Bechtol 2009). Good seed production data are lacking, but there is a record from southern California of an average of 7.2 kg (16 lb) of fruits per tree from velvet mesquite (Felker and others 1984). In the same record, other yield averages were 2.2 kg/ tree (5 lb) for honey mesquite, and less than 1 kg/tree (2.3 lb) for screwbean mesquite. Nopalitos “Nopales were grown and eaten as a vegetable in Central Mexico.” They are common in the wild and in backyards, and can be eaten grilled, boiled or sauteed (Bechtol 2009). Agave Hohokam cultivated Agave on dry marginal area, saving better soil conditions for more fickle plants. Loose rock terraces where constructed to capture some rainwater runoff, and the ground was likely mulched with rock. (Fish 2004)

Mark Moody uses drip irrigation to water his mesquite crops. Photo Credit: Mark Moody

Mesquite As one of the most diverse crops of the desert, mesquite can be used as human food, livestock feed, a nurse tree, and more. “Prosopis undoubtedly is the tree legume genus that has been most extensively used as human food. Prosopis was the food staple for Indians in the desert regions of Arizona, California, and

Honey Many of the flowering plants of the region offer nectar that makes unique and high quality honey. Mesquite nectar and blossoms produce a unique dark honey (Bechtol 2009).

A Sonoran Oasis Appendix E


Appendix F Compost Site Identification: http://www. pdf Determining your Compost Pad Size: http:// Highfields%20Pad%20Size%20Calculation%20 Worksheet.pdf Large-scale Composting Information and Options: y5104e/y5104e07.htm#bm07

Arizona State composting Laws: Title 3 (Agriculture), Section 3-112. Agricultural operations; nuisance liability A. Agricultural operations conducted on farmland that are consistent with good agricultural practices and established prior to surrounding nonagricultural uses are presumed to be reasonable and do not constitute a nuisance unless the agricultural operation has a substantial adverse effect on the public health and safety. B. Agricultural operations undertaken in conformity with federal, state and local laws and regulations are presumed to be good agricultural practice and not adversely affecting the public health and safety. Title 9 (Cities and Towns), Section 9-462.01, Subsection G G. No regulation or ordinance under this section may prevent or restrict agricultural composting on farmland that is five or more contiguous acres and that meets the requirements of this subsection. An agricultural


A Sonoran Oasis Appendix F

composting operation shall notify in writing the legislative body of the city or town and the nearest fire department of the location of the composting operation. If the nearest fire department is located in a different city or town from the agricultural composting operation, the agricultural composting operation shall also notify in writing the fire department of the city or town in which the operation is located. Agricultural composting is subject to sections 3-112 and 49-141. Agricultural composting may not be conducted within one thousand three hundred twenty feet of an existing residential use, unless the operations are conducted on farmland or land leased in association with farmland. Any disposal of manure shall comply with section 49-247. For the purposes of this subsection: “Agricultural composting” means the controlled biological decomposition of organic solid waste under in-vessel anaerobic or aerobic conditions where all or part of the materials are generated on the farmland or will be used on the farmland associated with the agricultural composting operation. Title 11 (Counties), Section 11-830. Restriction on regulation; exceptions; aggregate mining regulation; definitions Arizona state law exempts the following activities from composting regulations, “as long as they pose no public nuisance or health violation”: - Solid waste, which is composted as a volume reduction measure prior to intended disposal; - Backyard composting; - Normal farming operations or on-site disposal of yard waste or manure; - Composting of less than 3,000 cubic yards of yard waste or manure pre year provided acceptable methods of composting are used. The composting of yard waste into other usable materials such as mulch is not considered composting.

Appendix G Possible Additional Infrastructure While some food can be eaten right off the tree or out of the ground, processing and transportation infrastructure are often required to bring food from the farm to the table. Infrastructure categories sometimes necessary to make food systems operable include harvesting tools; washing and storage locations; refrigeration and freezing facilities; kitchen equipment; transportation methods; and more. For the purposes of this assessment, we have provided discussion and key references to some of these infrastructure requirements. Making use of existing infrastructure, such as the International Sonoran Desert Alliance’s community kitchen, would help keep new infrastructure requirements to a minimum. Church and school kitchens, extra restaurant and school refrigeration space, and community storage spaces, should all be explored. Storage Refrigeration and freezing are basic storage techniques to extend the life of many perishable food items, including fruits, vegetables, meat, and eggs. Commercial refrigeration in town to handle fresh food would increase its long-term availability. Since some restaurants in town close for the summer, it may be possible to rent some of their refrigeration and freezer space during this time to aid in food storage and preservation. In the winter, the cool desert temperatures are conducive to a well-insulated and shaded coldstorage facility to keep food cool and fresh. This simple technology requires just a building (which may be as simple as a prefabricated shed), insulation, and a fan to circulate air. Food drying may also be an economical and non-mechanical method of preserving food.

Sun-dried peppers and tomatoes are delicious preservation methods that are also known to have increased price value. The Tohono O’odham traditionally dried squash into long ropes called hihiwai that kept indefinitely (TOCA 2010). Processing The Tucson-based non-profit group Desert Harvesters owns a community hammermill which they transport to mesquite processing events around Tucson and southern Arizona. It is possible that Ajo could rent the Desert Harvesters’ hammermill for community events, but if Ajo is going to produce a commercial crop, or have reliable steady access to mesquite flour, the town will want to obtain its own mill. The Desert Harvesters’ community ownership model may be a viable way for the Ajo community to begin harvesting and eating locally produced mesquite. One new innovation created by a senior design team at Michigan Technological University is a prototype for a bicycle-powered hammermill, capable of grinding pods into flour just by pedaling (Michigan Tech 2010). It is unclear if and when this hammermill will become commercially available, but it might prove to be a low-cost method for grinding smaller amounts of flour on an as-needed basis—ideal for schools, restaurants or residential use. Slaughtering There are currently no slaughter facilities in the area. As a result of this lack of infrastructure “ranchers, sheepherders and their neighbors have lived, sometimes for years, without adequate access to their own meats (now slaughtered and processed in distant kill plants) or other healthy foods” (Nabhan 2011 14). Shipping cattle away from ranches, as is currently done on the Tohono O’odham nation, is a major revenue drain. A study by Ken Meter showed that “Coconino County ranchers and

A Sonoran Oasis Appendix G


farmers were losing $10 million by selling their products into the national commodity markets instead of directly marketing them to their neighbors” (Nabhan 2011, 15). Establishing a local slaughter facility would be a major boost for the local economy, and would make locally grown meat directly available to residents. According to Nabhan (personal communication 2011), between 50 and 100 livestock producers would be necessary partners to make a new small scale slaughter facility that handles five head of cattle per day viable. A more appropriately scaled option is the development of a mobile slaughtering unit. Taos County, New Mexico, has managed a similar mobile slaughtering unit that travels around the region and can process ten cows or eighty lambs per visit (Nabhan 2011, 15). “Other communities have opted to assist former game processors in scaling up to process livestock with state or federal inspection. This model has successfully been used by Perkinsville Meats in Yavapai County, Arizona, which recruited both small-scale beef and lamb producers at Canyon Country Fresh Network workshops help in Flagstaff” (Nabhan 2011 15). Distribution Groups like the Southwest Marketing Network are currently working to increase awareness of small, alternative, and innovative food producers in the Four Corners states of Arizona, New Mexico, Colorado, and Utah and might be a possible resource in helping get Tohono O’odham products in Ajo. This is just a start of the possible infrastructure requirements. Depending on the crop and scale, the infrastructure needs may swing wildly. Careful planning by looking at the entirely of a food system, from farm to plate, will be necessary.


A Sonoran Oasis Appendix G

A sonoran Oasis Developing a Local Food System for Ajo, Arizona

Deep in the Sonoran Desert, the community of Ajo, Arizona, is facing health and economic challenges. Ajo is dependent on the continued availability of imported foods, leaving people vulnerable to conditions over which they have little power. Productive and ecologically sound land use is achievable through modern adaptations of traditional Sonoran Desert farming and water management techniques that maximize food production while respecting the limits of the desert.

The Conway School of Landscape Design is the only institution of its kind in North America. Its focus is sustainable landscape planning and design. Each year, through its accredited, ten-month graduate program just eighteen to nineteen students from diverse backgrounds are immersed in a range of applied landscape studies.

Ahron Lerman | Susannah Spock | Sean Walsh

Conway School of Landscape Design Winter 2011

A Sonoran Oasis: Developing a Local Food System for Ajo, Arizona  
A Sonoran Oasis: Developing a Local Food System for Ajo, Arizona  

Deep in the Sonoran Desert, the community of Ajo, Arizona, is facing healthand economic challenges. Ajo is dependent on the continued availa...