CATTAILS TYPHA LATIFOLIA
SUGARCANE SACCHARUM OFFICINARUM
RATE OF RHIZOME GROWTH
RATE OF RHIZOME GROWTH
LOW
MAINTENANCE NEEDS OPTIMAL WATER LEVEL
HIGH MED
SALINITY TOLERANCE GREYWATER TOLERANCE EROSION CONTROL RESILIENCE TO DISRUPTION
HIGH MED LOW MED
MAINTENANCE NEEDS
MED LOW
OPTIMAL WATER LEVEL SALINITY TOLERANCE
HIGH LOW
GREYWATER TOLERANCE EROSION CONTROL RESILIENCE TO DISRUPTION
MED LOW HIGH
Phytohydraulics Sea level rise and flooding are issues of critical concern in Miami Beach. High tide levels have increased annually by almost an inch in the Miami area (Kolbert 2015, 42). What if Miami Beach specified rhizomatous, salt-tolerant grasses as a form of urban adaptation? Encouraging pervious surfaces would increase water absorption rates despite tourism-related disturbances. By taking cues from Everglades’ sawgrass, plant species with dependable root mass could help alleviate localized flooding. This project proposes the strategic use of roots in Miami Beach to help manage some of the city’s frequent flooding events. Comparable to using cattails to soak up phosphorus, rhizomatous grasses can be used to soak up large amounts of superficial water. Known as phytohydraulics (Kennen and Kirkwood 2015, 39), “each year, plants in North America move more water than all the rivers in North America combined” (Kennen and Kirkwood 2015, 29). And there are other benefits. Grasses can be irrigated with greywater, helping to preserve limited supplies of freshwater. Plants also become community assets that offer educational opportunities and new habitats, all while improving soil quality and countering erosion and the urban heat island effect.
Grasses are well equipped for plant competition and external disturbances because they spread quickly in resilient, monotypic mats (Arber 1934, 323). A comparison of several rhizomatous grasses shows that paspalum would be particularly well suited the conditions in Miami Beach. Durable paspalum rhizomes could be integrated into the city as green roofs, green walls, green patios, green parking lots, and green sidewalks. Any previously impervious surface would become porous. This strategy could also be incorporated with other resiliency measures: for example, an add-on green wall could include a temporary window cover that would soak up more water and help protect against hurricane force winds. Provincetown, MA used to have a “Beach Grass Committee” responsible for planting Marram-grass on uncovered sand (regardless of property lines) in order to avoid sand-storms (Arber 1934, 339). A similar committee could be created for Miami Beach. Imagine the city draped in grass. By echoing the properties of sawgrass and increasing the city’s levels of porosity, rhizomatous plants like paspalum can tackle flooding in Miami Beach armed only with the power of a single root system.