|STETTLER, JASON - Utah State University|
|MACADAM, JENNIFER - Utah State University|
Submitted to: International Rangeland Congress
Publication Type: Proceedings
Publication Acceptance Date: 3/8/2016
Publication Date: 7/8/2016
Citation: Johnson, D.A., Stettler, J.M., Macadam, J.W., Bushman, B.S., Connors, K.J., Jones, T.A. 2016. Evaluation of indigenous Lotus species for the western USA for rangeland revegetation and restoration. In: A. Iwaasa, H.A. Lardner, M. Schellenberg, W. Willms, and K. Larson (eds). The Future Management of Grazing and Wild Lands in a High-Tech World: Proceedings 10th International Rangeland Congress, Saskatoon, Canada. International Rangeland Congress. 283-285.
Interpretive Summary: Semiarid rangelands in the western U.S. are facing serious challenges related to past mismanagement, invasive weedy species, wildfires, and climatic change. Legumes native to the western U.S. are of interest for revegetation of these rangelands because they provide biologically fixed nitrogen, increase plant production, enhance forage quality, and provide important food sources for grazing animals, wildlife, and pollinators. However, seeds of only a few native legume species are currently commercially available. Seed collections of two native species (Utah lotus and scrub lotus) were made across Utah, Nevada, and Arizona. Seeds from the collections were germinated, grown in a greenhouse, and transplanted into common gardens at three sites in northern Utah. Collections varied for seed-pod weight, plant, height, and dry-matter yield. Seed of top-performing collections of Utah lotus for the south-central Wasatch Mountains of Utah are being increased for further testing prior to commercial release.
Technical Abstract: Semiarid rangelands in the western USA are facing serious challenges related to past mismanagement, invasive weedy species, wildfires, and climatic change. Leguminous forbs that are native to the western USA are of interest for rangeland revegetation and restoration because they provide biologically fixed nitrogen, increase plant production, enhance forage quality, and provide important food sources for grazing animals and pollinators. However, seeds of only a few legume species native to the western USA are currently available commercially for use on rangelands in the Great Basin and Colorado Plateau. In 2012, a total of 19 seed collections of Utah lotus (Lotus utahenis Ottley) and scrub lotus (L. wrightii [A. Gray] Greene) were made across Utah, Nevada, and Arizona. In May 2013, greenhouse-grown plants were transplanted into common-garden plots at three sites in northern Utah. Taxonomic verification of the collections indicated that 14 collections were Utah lotus and five collections from Arizona were scrub lotus. Selected data from 2014 at the Millville site indicated that collections within species varied significantly (P<0.001) for seed-pod weight, plant height, and dry-matter yield. All collections had relatively high levels of condensed tannis, a class of polymeric flavanoids that can reduce the risk of bloat in grazing animals lead to more efficient use of forage protein and suppress internal parasites in grazing animals. Concentrations of CT varied significantly (P<0.001) between species and among collections within species with values ranging from 14 to 18 % dry matter. Collections of Utah lotus from the south-central Wasatch Mountains of Utah were in the top tier of collections, and seed of these collections are geing increased for further testing prior to commercial release.