Enhancing rangeland plant diversity is a positive step to increasing animal diversity and productivity. Adding or strengthening a shrub canopy, defined as 1-3 m, may compliment diversity beyond the traditional herbaceous or arboreal layers. As an example, the wide range of native perennial, shrubby legumes in Texas indicates untapped potential for multiple uses such as forage, ecosystems services, wildlife habitat, fuel, and possibly pulse crops. There are over 30 shrub or short tree legume genera in Texas, many with multiple species. Our program seeks to identify, collect, characterize, domesticate and commercialize native Texas shrub legumes that could lead to multiple benefits in rangeland ecosystems. This could foster greater ruminant species diversity on rangelands, ranging from selective to bulk browsers and grazers that could specialize in herbaceous, shrub and arboreal canopies, each contributing to greater herbage and animal productivity than mono-canopy systems. This approach could be applied in many rangeland ecosystems in North America and throughout the world. Information on Texas native shrub species is sparse but builds on previous research on Desmanthus spp., Leucaena retusa (golden-ball leadtree) and woody ecotypes of Acacia angustifolia var. hirta (prairie acacia). The latter is currently grown commercially for seed production as shrubby Rio Grande Germplasm and herbaceous Plains Germplasm. The greatest successes have come from managing these for monoculture seed harvest or white-tailed deer plots rather than reseeding degraded rangeland or re-establishing native savannahs. Challenges identified to date include extensive armor (thorns), chemical protection (anti-quality factors such as condensed tannins), poor seed germination, slow establishment, low feed value (e.g. lignins), and limited market to motivate commercial seed companies. Our native legume shrub domestication program is currently in the early identification and collection phases while characterizing the agronomy of select genera including Sephora, Styphnolobium, Gleditsia, and Leucaena spp.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.