2012 Annual Report
1a.Objectives (from AD-416):
The University of Nevada at Reno is undertaking a cooperative project with the Agricultural Research Service and to investigate (1) the ability of key Great Basin native annual species to compete with cheatgrass as well as (2) their ability to facilitate the establishment of Great Basin native perennial bunchgrasses. The ultimate goal of this project is to assess the suitability of key Great Basin native annual species for use in restoration seedings.
1b.Approach (from AD-416):
The University of Nevada at Reno will assist in developing, implementing, and analyzing experiments to assess the ability of Great Basin native forb species to compete with cheatgrass and facilitate establishment of native perennial grasses. This will include collaborating with ARS on greenhouse and field experiments, as well as the writing of scientific manuscripts.
This research supports objective 1: Identify and characterize biotic and abiotic conditions and processes that affect plant community factors and ecosystem dynamics on healthy and degraded rangelands to improve the ability to predict how rangelands will respond to changing environmental conditions and alternative management practices. Specifically Sub-objective 1.1: Determine how land management history, the reproductive ecology of invasive annuals, and biotic interactions affect the structure and function of selected Great Basin ecosystems.
This research examines an ecologically and economically rational strategy for management of B. tectorum invaded rangelands. By utilizing principles of natural succession of Great Basin rangelands, two goals are met: (1) restoring rangelands to their proper functioning using native plant materials and (2) an ecological and economic benefit to land managers through increased restoration success. Understanding if native annual forbs can increase establishment of E. multisetus in degraded rangelands will allow managers and seed producers to take the following steps to maintain healthy systems: (1) include highly competitive annual forbs in restoration of seed mixes to promote establishment of early successional perennial grasses such as E. multisetus, (2) target annual forbs that have the greatest positive effect on E. multisetus and negative effect on B. tectorum biomass and reproduction for seed increase programs, and (3) manage and maintain sites with high annual forb diversity, as these populations may be a vital component for successful restoration of disturbed rangelands.
The greenhouse and field experiments have been completed, and data has been analyzed. The results of these experiments support the idea that the presence of certain native annual forbs can enhance the establishment of E. multisetus in B. tectorum invaded rangelands. A manuscript entitled: “Native annual forbs reduce Bromus tectorum biomass and indirectly facilitate establishment of a native perennial grass” is in review at the Journal of Applied Ecology.