Slender rush-pea (Hoffmannseggia tenella) is an endangered herbaceous legume endemic to southern Texas. Agricultural expansion and invasive nonnative grasses have caused reductions in its range, threatening existing populations. We compared three management techniques that control competition to no management (control) to determine effects on slender rush-pea survival and morphology. We treated some slender rush-pea plants with summer prescribed burning. In the mechanical treatment we controlled above-ground competition surrounding target slender rush-pea plants with a string trimmer and we removed both above- and below-ground competition with herbicide in the chemical treatment. No slender rush-pea plants died during our two-year study. Plants in each competition removal treatment produced more main stems than control plants at various times throughout the study. Summer prescribed burning produced longer stems, while both summer burning and chemical treatment resulted in more leaves on the longest stem and more flowers than control plants at various times throughout the study. Slender rush-pea individuals with more main stems, longer stems, and more leaves may be more robust and resilient to environmental stress. We speculate increased flower production may indicate enhanced reproduction. At the pasture scale herbicide treatment is not practical as it may eradicate remaining native plants. Summer prescribed burning may be the most effective method for increasing short-term robustness of slender rush-pea; mowing could be a temporary substitute when fire is impractical. Results indicate that slender rush-pea benefits from active management and control of competition from nonnative grasses, and if managed properly slender rush-pea could persist in their presence.
How to translate text using browser tools
1 July 2017
Evaluating Removal of Competition on Morphology of Endangered Slender Rush-Pea (Hoffmannseggia tenella) Endemic to Southern Texas, USA
Ashley C. McCloughan,
Sandra Rideout-Hanzak,
David B. Wester,
Weimin Xi
ACCESS THE FULL ARTICLE
Natural Areas Journal
Vol. 37 • No. 3
July 2017
Vol. 37 • No. 3
July 2017
endangered
herbaceous legume
Hoffmannseggia tenella
prescribed burning
removal of competition
