Native Plant Materials for Ecological Restoration of Degraded Drylands

Science Center Objects

There is a growing consensus among resource managers to use native plant materials for ecological restoration of degraded drylands. Some plant species may be suitable for re-introduction across broad environmental gradients. Other species may fail under narrower conditions, or their re-introduction may have genetic consequences for local ecotypes, particularly when adapting to future climate changes.  In coordination with the Bureau of Land Management, USGS is developing science-based priority species lists for native plants used in restoration, developing seed transfer zone guidelines and distance-based tools for managers collecting and using native seeds in restoration, evaluating local adaptation of native species across a network of common gardens across the Mojave Desert, and expanding these efforts to the Sonoran Basin and Range ecoregion. 

Graduate student measures physiological, morphological, and phenological traits of shrub

Graduate student Nathan Custer (Texas State University, San Marcos) measures physiological, morphological, and phenological traits of the shrub white bursage (Ambrosia dumosa) to inform managers how far seeds can be collected and used for re-seeding disturbed areas across the ecoregion while minimizing restoration failure. (Credit: Lesley DeFalco, USGS WERC. Public domain.)

Science-based approach for BLM’s Mojave Desert Native Plant Program

Native plant programs are well-established for the Great Basin and the Colorado Plateau, but no formal programs existed for the warm deserts of North America until recently. Dr. Lesley DeFalco and USGS scientists partner with Bureau of Land Management, US Fish and Wildlife Service, Rancho Santa Ana Botanic Garden, Texas State University – San Marcos, and NRCS Tucson Plant Materials Center to develop science-based approaches for compiling priority species lists and developing seed transfer guidelines for restoring damaged Mojave Desert shrublands. Through partnerships with federal, state, and county agencies, USGS and collaborators established a network of 10 common gardens throughout the Mojave Desert ecoregion. This network represents the range of environmental variability for determining local adaptation across multiple plant functional groups. Landscape genetic approaches complement common garden efforts and are helping to distinguish which species are suitable for wildland seed collections and for commercial seed production. This project is developing GIS-based tools for identifying and interpreting seed transfer zones for managers so that genetically appropriate seed sources are used to restore damaged Mojave Desert shrublands as regional climate continues to change.

Mojave Desert Spatial Tool Figure

Interactive, distance-based tools that are based on genetic information enable managers to make timely, informed seeding decisions for ecological restoration in the Mojave Desert ecoregion (From Shryock et al. 2016, Ecol. Applications 27:429-445). (Public domain.)

Provisional seed transfer zones for the Sonoran Basin and Range

With the emerging approach to develop plant materials for the Mojave Desert, USGS is working with California BLM to extend our science-based plant materials program for the Sonoran Basin and Range, with particular focus on the Colorado Desert of California. This project aims to develop a priority species list of important native species and develop provisional seed transfer guidelines for collecting and using plant materials for restoration of disturbed Sonoran Basin and Range habitats. The priority list includes native species that promote pollinators, are known to have high recovery and restoration success, and have known germination and establishment requirements.