Making a difference: the small but meaningful Cadereyta Regional Botanic Garden
In grateful memory to the life and achievements of Dr. Jerzy Rzedowski Rotter (1926–2023)
Introduction
Small but neat and cozy, the Cadereyta Regional Botanic Garden (CRBG) is a public institution renowned for the ex situ conservation of flora from the southern end of the Chihuahuan Desert in Central México.
The CRBG belongs to the Querétaro State Council of Science and Technology (CONCYTEQ). It is organized into three interrelated aspects: ex situ conservation, scientific research, and environmental education. At the heart of its duties lies the development and the maintenance of a collection of plants that has multiple purposes: ex situ preservation of specimens; a living bank of germplasm for propagation; a data source for long-term, systematic observation; a cloister for education, training, and awareness; and a beautiful setting for recreation and reconnecting with nature.
This paper offers a bird’s eye view of the collection, which features a stunning array of 320 taxa from 30 plant families, organized according to scientific, educational, and geographic criteria. We also describe the ambiance and features of each section. The botanic garden’s visitors are offered guided tours and receive an awareness-raising message on the arid plant diversity and the conservation efforts done here. Have a glance.
1Cadereyta Regional Botanic Gardens, Querétaro, México email: bmaruri@concyteq.edu.mx
Plant diversity at the Southern end of the Chihuahuan Desert
The area of influence of the CRBG is in the discontinuous southern end of the Chihuahuan Desert, known as the Semi-Arid Zone of Querétaro and Hidalgo (SAZQH) (Rzedowski 1978, HernándezOria et al. 2007).
The region is at the crossing point of three physiographic provinces: The Eastern Sierra Madre, the Trans-Mexican Volcanic Belt, and the Central Plateau. This results in a combination of sedimentary and volcanic lithology on which only minor or moderate development soils are established. The mountainous surface lies between 1,450 and 2,100 meters above sea level. The prevailing climate is temperate and semidry, with summer rains. (BS1kW type, according to the update from Köppen climate classification proposed by Enriqueta García (2004) for México).
This heterogeneity facilitates a mosaic of plant communities (Zamudio et al. 1992, HernándezMagaña et al. 2012) with a remarkable concentration of members of the Cactaceae family (HernándezMartínez et al. 2020), and other succulent plants (Fig. 1). The SAZQH hosts slightly more than 60 taxa of this family, including species with different distribution ranges, sizes, shapes, threat levels, and some noteworthy endemisms (Sánchez et al. 2006).
The first botanic garden of the state of Querétaro
The CRBG history indirectly started in 1988. By then, the most renowned Mexican botanist, Polish-born Dr. Jerzy Rzedowski, was pushing his project “Flora del Bajío y Regiones Adyacentes.” He fostered the establishment of an herbarium with local authorities, and convened a meeting with local specialists of flora, who recommended several tasks to pursue the conservation of local flora. Eventually, Dr. Rzedowski’s request became the foundation of a larger, complex project that led to the creation of the “Centro Queretano de Recursos Naturales” (CQRN) (Querétaro Center for Natural Resources), which was officially decreed in 1990 (Serrano-Cárdenas and Pelz-Marín, 2017). The late Dr. Gabriel SiadeBarquett, then director of the CONCYTEQ, planned the structure of the CQRN, including both the QMEX herbarium and the CRBG on its “renewable resources” section (CONCYTEQ, 2016).
A subsequent collaboration between the Cadereyta Municipality, the Ejido2 “Las Fuentes y Pueblo Nuevo” and the CONCYTEQ materialized the CRBG, which opened to the public in April 1991. The botanic garden dedicated its first twelve years collecting live specimens and herbarium vouchers. Since 2003, the Directorate
2An ejido is a type of communal land tenure.
has implemented a strategic plan with specific lines of work, procedures, compliance deadlines, and physical resources required to achieve goals. The CRBG’s goals and tasks are grounded in the institutional mission: “Serve the development of the state of Querétaro through the generation of greater scientific knowledge and conservation of its plant resources.” (Fig. 2).
A section-by-section tour through the living plant displays
Planned, built, and maintained according to rigorous international standards and scientific criteria, the living collection of plants is a place for experiencing, discovering, and understanding arid plant diversity through the senses. It is itself a gorgeous landscape established in gentle volcanic slopes. To the Southeast, a cliff is the natural limit from the outside and a stunning scenario seen from different standpoints. Visitors walk through small cobblestone pathways surrounding planters, skillfully constructed as giant steeped-steps ascending the slopes. A skilled guide will explain the botanic garden’s mission and achievements, but most importantly, about the collection, its sections, its distinguished guests, and their importance. The living collection of the CRBG is divided into seven sections, each with a specific purpose. Together they represent a sample of the plant diversity in the Semiarid Zone of Querétaro and Hidalgo and the State of Querétaro (Sánchez, 2015).
The semiarid zone’s emblematic families
This section aims to correct a common misperception regarding the narrow plant diversity of semiarid places. Hanging on the walls of this cloister, a series of ten posters are available for visitors that present, explain, and illustrate the leading botanical families of the SAZQH. On the ground, a representative group of the semiarid flora ensemble greets the visitors. The display includes columnar plants such as Lophocereus marginatus (D.C.) S. Arias & Terrazas, Dasylirion longissimum Lem., Dasylirion acrotrichum (Schiede) Zucc.; candelabra-shaped cactus such as Myrtillocactus geometrizans (Mart. ex Pfeiff) Console, barrel cactus as Ferocactus histrix (D.C.) G.E. Linds., and Echinocactus platyacanthus Link & Otto. The garden’s library is on one side of the cloister, and interested visitors are welcome to browse through the books.
The Semidesierto of Querétaro and Hidalgo
The rounded shape of this planter reminds a viewer of the Sun, which makes the place an excellent location to learn about the essential plant processes related
to sunlight. Plants transform water and carbon dioxide into organic compounds, releasing oxygen into the atmosphere. Plant families that live in semiarid environments face drought challenges, and, therefore, they have adaptations to store and use water efficiently. Here, a group of impressive plants that illustrate these adaptations is displayed in concentric planters. Examples include columnar cactus (Isolatocereus dumortierii (Scheidw.) Backb., “Órgano”); globe-shaped plants (Kroenleinia grusonii (Hildm.) Lodé, “Barril de Oro”; Echinocactus platyacanthus Link & Otto, “Biznaga burra”; Ferocactus histrix, “Guamishi”); candelabra-shaped examples (Myrtillocactus geometrizans, “Garambullo”); paddleshaped (Opuntia Mill. sp.); rosettes (Agave garciae-mendozae Galvan & L. Hern., “Maguey”, Dasylirion acrotrichum, “Cucharilla”, Yucca filifera Chabaud, “Izote”, Yucca
queretaroensis I.Piña, “Estoquillo”); prickly-stemmed, deciduous (Fouquieria splendens Engelm., “Chiquiñá”); and waxy-stemmed (Euphorbia antisyphilitica Zucc., “Candelilla”). (Fig. 3).
The corridor
Behind the parking lot, at the lower part of the collection, a row of nineteen Cephalocereus polylophus Britton & Rose escorts two barrel cacti of the Echinocactus platyacanthus (“Biznaga burra”). Another highlight of this corridor is a Pseudobombax ellipticum (Kunth) Dugand, whose spectacular long-stamened late winter flowers have earned it its name, “Shaving Brush.” The corridor is a popular photographic opportunity for visitors of all ages. (Fig. 4).
Cactaceae of Querétaro
The planters’ arrangement in staircase steps presents the main types of arid scrublands of the SAZQH. The Cactaceae have the leading role in this section, displayed as centerpieces of the four main types of xerophytic3 scrub vegetation. This most extensive section allows visitors to appreciate the ten percent4 of all Mexican cacti which are distributed in Querétaro. This section route resembles a trip throughout the state, from the center to
3 xeros, “seco” y phytos; Therefore, the xerophytic scrub is a type of vegetation typical of arid zones, characterized by species adapted to high temperatures and short and scarce rainy seasons. Depending on the predominant species, there are various subtypes: e.g., microphyllous xeric scrub, rosetophyllous xeric scrub, crasicaule xeric scrub.
4 This percentage is as high as 14%, depending on which taxa are considered subspecific. 10% remains as indicative.
the northeast, ascending longitudinally through the Sierra Gorda mountains. (Fig. 5).
Crasicaule scrub: This vegetation type is widely distributed in central and southern Querétaro, flourishing over volcanic rocks and soils. Columnar or pad-shaped plants of the Cactaceae visually dominate this scrub, along with massive tropical trees like Yucca filifera or Ipomoea murucoides Roem. & Schult. This part of the garden displays monumental columnar, paddle-like, and candelabra-like cacti such as Lophocereus marginatus, Opuntia tomentosa Salm-Dyck, O. robusta J.L. Wendl. Ex Pfeiff., Myrtillocactus geometrizans, and Opuntia karwinskiana Salm-Dyck. Barrel cactus as Ferocactus latispinus Britton & Rose and Ferocactus histrix are present, along with smaller species like Stenocactus obvallatus A. Berger, Echinocereus cinerascens Lem., Acanthocereus tetragonus (L.) Hummelinck and cespitose, clumping cacti such as Mammillaria compressa DC., among others. (Fig. 6).
Microphyll scrub: The next two planters display this extremely arid type of vegetation. It is restricted to the Extoraz and Moctezuma River basins in the Cadereyta and Peñamiller municipalities of Querétaro. The woody members of the scrub reach up to five meters in height and distribute scarcely, leaving open spaces between them. Some examples are: Lippia origanoides Kunth, Karwinskia humboldtiana (Schult.) Zucc., Bursera fagaroides Engelm., Painteria revoluta Britton & Rose, and Mimosa monancistra Benth. They accompany Cactaceae like Mammillaria elongata DC., Astrophytum ornatum (DC.) Britton & Rose, Opuntia microdasys (Lehm.) Pfeiff., and O. robusta. Some original hillside rhyolitic boulders can still be seen protruding from these planters.
Rosetophyll scrub: This type of scrub is represented by very noticeable species which distribute in a specific altitude range where mist and fog is the most available water. Rosette structures cause condensation of water, which drips into the soil. Those rosette shapes, monumental inflorescences, and massive vegetative seedlings catch the eye of visitors. The paths around this part are slightly uneven, which adds to the feeling of adventure. The top representatives of this type of vegetation are Agave striata Zucc., Dasylirion longissimum, Dasylirion acrotrichum, Hechtia podantha Mez, well accompanied by cacti such as Opuntia stenopetala Engelm., Thelocactus leucacanthus Britton & Rose, Astrophytum ornatum, and companion species such Fouquieria splendens, Dodonaea viscosa Jacq., and the short, but very interesting Jatropha dioica Sessé (Fig. 7).
Submontanous scrub: This is a less arid type of semiarid scrub and distributes just below temperate
forest (Quercus L. forest). This scrub can be found in the humid tropical municipalities of Querétaro, Landa de Matamoros, Jalpan de Serra, and Arroyo Seco. However, it also distributes in the SAZQH in Cadereyta de Montes, Peñamiller, and San Joaquín. It is an evergreen type of vegetation, where species have small leaves. Still, it hosts one of the remarkable examples of the arid flora in the SZAQH: Yucca queretaroensis. (Fig. 8). Other species in this section are Senegalia reniformis Britton & Rose, Hechtia argentea Baker, Ditaxis heterantha Zucc., Beaucarnea hookeri Baker, Fouquieria fasciculata Nash, Senna wislizeni (A.Gray) H.S.Irwin & Barneby , and cacti species such as Ferocatus glaucescens Britton & Rose, Astrophytum ornatum and Opuntia tomentosa
Two sections of “biznagas” (barrel cacti) delimit the Cactaceae of Querétaro. The Western side has a unique boundary: an elongated planter embracing dozens of Kroenleinia grusonii, “Golden barrels” that seem to descend through the slope. Several of these individuals came from their destroyed habitat, the Infiernillo Canyon, which was flooded to build the “Zimapán” dam in the 1990s. K. grusonii became a symbol for the conservation of this family and is currently on the list of NOM059-SEMARNAT-2010, with category P (in danger of
“Cactáceas
extinction), and within Appendix II of the CITES list (Hernández-Martínez et al., 2020). (Fig. 9).
The Eastern boundary is another elongated planter with Ferocactus histrix, “Guamishí.” Like other barrel cacti, this species has been traditionally used as a source of flesh for the Mexican delicacy “acitrón”, a candy made with cacti pulp slowly cooked in sweet, thick syrup. “Guamishí” also refers to its fruit: a sweet, fleshy, yellow berry, locally used for ice cream, lollipops and refreshments. The species is currently listed as Pr (special protection) on the list of NOM-059-SEMARNAT-2010 (Hernández-Martínez et al., 2020). (Fig. 10).
Agavoideae (Asparagaceae) of Querétaro
Halfway through the trek up the hills of the CRBG, in the Southeastern extreme of the living collection, the visitors can appreciate the beautiful geometry of the Agavoideae species. The slope at this point is steep. (Fig. 11).
The state of Querétaro has a noteworthy cast of Agavoideae species, representing 16% of Mexican species. This section has 37 taxa of 6 genera [Agave L. (“Maguey”, “Pita”), Beschorneria Kunth (“Falso agave”), the former
Manfreda Salisb., (“Amole”), Polyanthes Jacq. (“Nardo”), and Prochnyanthes S. Watson (“Amoles”)5 genera, and Yucca L. (“Izote”, “Estoquillo”)]. Planters are organized according to taxonomic criteria: Agaves are grouped by subgenera (Agave: Salmianae, Americanae, Ditepetale, Rigidae, and Sisalanae; Littaea: Marginatae, Filiferae, Striatae, Polycephalae). These plants are historically linked to several cultures of the Central Plateau and the semiarid places of México, whose inhabitants found food, heat, roof, clothing, medicine, drink, ornament, furniture, agricultural implements, and other diverse uses in them.
5 Recently migrated to the Agave genus.
Trees of the Querétaro Valley
At this point, the reader might think that the collection is just about plants from arid places. This section steps out of the line because the type of vegetation represented is less arid than the rest. In the Western part of the Querétaro, on the outskirts of the capital city, some relicts of the seasonally dry forest lie ahead (Sánchez et al. 2011). Its aspect offers a drastic change according to the season: during late Autumn, Winter, and early Spring, it shows a misleading gray, lifeless appearance. Spring makes many species of plants bloom, and summer’s rainy season covers its canopies with dense, bright green foliage. (Fig. 12).
In contrast to other sections of the living collection at the botanical garden —which shows individuals that were recollected in their natural habitats— this one displays trees grown from seed, dismantling the deeply rooted myth about the slow growth rate of native flora.
Visitors can meet here species of the Fabaceae family, such as Albizia occidentalis Brandegee, Leucaena leucocephala (Lam.) de Wit, Vachellia schaffneri (S.Watson) Seigler & Ebinger, Mimosa aculeaticarpa Ortega, Prosopis laevigata (Humb. & Bonpl. ex Willd.) M.C.Johnst., Senna polyantha (Coll)
H.S.Irwin & Barneby, Zapoteca formosa (Kunth) H.M. Hern.; Cactaceae such as Echinocereus cinerascens , Ferocactus echidne (DC.) Britton & Rose, F. histrix , Isolatocereus dumortieri, Myrtillocactus geometrizans , several Opuntia species. Other families represented are Convolvulaceae ( Ipomoea murucoides), Meliaceae ( Cedrela dugesii S. Watson), Rhamnaceae ( Condalia mexicana Schltdl., C. velutina I.M. Johnst., Karwinskia humboldtiana , Rosaceae ( Malacomeles denticulata (Kunth) G.N. Jones), Sapindaceae ( Dodonaea viscosa ), Verbenaceae ( Lantana achyranthifolia Desf., L. camara L.), among others.
Mammillaria in México
This section is a practical example of using native flora from Queretaro to improve the environment and resembles a reconstruction of the seasonally dry forest. This section is a surprising garden piece. The species of the Mammillaria Haw. genus are small and inconspicuous. For the non-trained eye, walking through this section might seem like a rocky garden. (Fig. 13). However, nearly 80 taxa of small, globose “biznaguitas” of the genera Cochemiea (K. Brandegee) Walton and Mammillaria are displayed.
This section offers an excellent opportunity to practice the human ability to classify organisms and understand and appreciate their similarities and differences. It is a good place to know why it is essential to classify organisms as well. Each planter exhibits a group of species that belong to a Series. This
means that plants are grouped with their close relatives. The names of the Series are related to the plant characteristics. Some examples are Series Longiflora (with long, big floral structures); Series Proliferae (with a significant capacity to produce vegetative offspring); Series Leucocephalae (with a considerable number of white, radial spines), Series Polyedra (with angled tubercles) or Ancistracanthae (with hook-shaped spines).
The star of this section is the very threatened Mammillaria herrerae Werderm., the subject of sustained efforts for its ex situ conservation. This little beauty faces adverse factors for its survival in situ. A few wild individuals are separated into small, scattered groups. The wild individuals live in a significantly reduced area and are under pressure due to the illegal extraction of individuals, and land use change.
The garden of hummingbirds and people
The Cadereyta Regional Botanic Garden hosts eight species of hummingbirds, both resident and
migratory species that travel from long distances. This is the case of the Selasphorus rufus , or Rufous hummingbird, a small bird that nests in the Northwest of Canada and the United States, including Alaska; then, it migrates South of the border, reaching several mountainous areas in México. This charismatic species became a majestic cartoon character that welcomes visitors to this planter. The Garden of Hummingbirds and People is a living classroom in which learning and reflection merge in the mind of the user on the appreciation of hummingbirds through knowledge of their characteristics, their role in local ecosystems, and their migratory habits; and through reflection on the actions that human beings can carry out both in favor of their conservation and against it. (Fig. 14).
The plant propagation unit
Plant reproduction and cultivation are keystones of flora conservation at the Cadereyta Regional Botanic Garden. A central garden’s area of focus is the
development of optimal propagation protocols, and today, over one hundred species are reproduced here. Priority botanical families for reproduction are Agavaceae, Cactaceae, and Fabaceae, and fifteen additional families that grow in the Semiarid Zone of Querétaro and Hidalgo. (Figs. 15–17).
In the botanical garden, a method has been devised to propagate plants. The technique uses mainly seeds of the species, which are put to germinate, with or without previous treatment. For species whose germination is complicated, asexual reproduction methods have been tested using cuttings or stem portions. The most difficult cases have been addressed by micropropagation, carried out in collaboration with other local institutions.
Greenhouses can be seen as “plant factories”, and as a place for Environmental education. People can connect with plants and create a constructive dialogue about plant diversity and conservation. Cultivated plants are available for visitors to make a conscious and informed purchase, better considered as responsible plant ownership than a commercial transaction. It is, in fact, a very supportive action for conservation: conscious trade helps lower pressure on natural populations for illegal poaching. In a guided tour, this is the last station and reinforces the educative model at the garden.
The Cadereyta Regional Botanic Garden is paradoxical. Being a garden, it flourishes and offers its wondrous beauty throughout the year. As a collection of arid plants, it shows how well-adapted plants are to their dry environment. These are tough, robust species. Visitors usually leave with a new panoramic view of the importance of arid biodiversity. We try to convince them to contribute to its conservation in their everyday lives. We offer the best that we have, in the living collection of plants, in the wild landscape that visitors encounter, and in the daily tasks we undertake to pursue the conservation of the valuable plants of the extreme South of the Chihuahuan Desert.
l iter Ature cited
CONCYTEQ. 2016. Reseña histórica 1986-2016. Consejo de Ciencia y Tecnología del Estado de Querétaro. García, E. 2004. Modificaciones al Sistema de Clasificación Climática de Köppen. Quinta edición. Universidad Nacional Autónoma de México, México. Hernández-Martínez, M. M., J. Golubov-Figueroa, M. C. MandujanoSánchez, B. Maruri Aguilar, et al. 2020. Querétaro Semidesert: Cactaceae Imperiled, reference module in Earth Systems and Environmental Sciences, Elsevier. Elsevier (ScienceDirect): 1–16. https://doi.org/10.1016/B978-0-12-821139-7.00074-X. Dominick A. DellaSala and Michael I. Goldstein, eds.
16. The plant propagation unit, one of the most enjoyable places to visit at the CRBG. Visitors learn here about the propagation protocols, and can make a conscious, informed, committed acquisition of a plant.
17a. Plants produced at the CRBG are tagged with the approval number given to the CRBG as a “UMA” (Management unit for wildlife conservation) of the Mexican Ministry of Environment and Natural Resources. The tags accredit the legal provenance of plants reproduced at the garden.
17b. High horticultural standards are maintained through propagation processes.
Hernández-Oria, J. G., R. J. Chávez, and E. Sánchez. 2007. Factores de riesgo en las Cactaceae amenazadas de una región semiárida en el sur del Desierto Chihuahuense, México. Interciencia 32:728–734.
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Sánchez Martínez, E., J. G. Hernández-Oria, M.M. Hernández Martínez, B. Maruri Aguilar, et al. 2011. Técnicas para la propagación de especies nativas clave para la forestación, la reforestación y la restauración en el municipio de Querétaro y su área de influencia. Consejo de Ciencia y Tecnología del Estado de Querétaro, México.
Sánchez Martínez, E. 2015. El Jardín Botánico Regional de Cadereyta: un espacio visual y contextual para la flora de Querétaro. Consejo de Ciencia y Tecnología del Estado de Querétaro.
Serrano Cárdenas, V. and R. Pelz Marín. 2017. Herbario de Querétaro “Dr. Jerzy Rzedowski” (QMEX). Universidad Autónoma de Querétaro, Editorial Universitaria. México.
Zamudio, S., J. Rzedowski, E. Carranza, and G. Calderón. 1992. La vegetación del estado de Querétaro. Consejo de Ciencia y Tecnología del Estado de Querétaro, México.
Photos courtesy of CRBG photo stock.