Restoring rangelands from cheatgrass infestations

Authors: Harmon, Daniel - Dan; Clements, Darin - Charlie

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/20/2022
Publication Date: 10/18/2022
Citation: Harmon, D.N., Clements, D.D. 2022. Restoring rangelands from cheatgrass infestations. Meeting Abstract. 22:6.

Interpretive Summary:

Technical Abstract: Recent estimates predict that at least 20% of the Great Basin is dominated by the exotic invasive annual, cheatgrass (Bromus tectorum). Based on data from the Rangeland Analysis Platform (RAP) shrub/grassland habitats in poor condition in Nevada have increased 4-fold in the past 30 years from 10% (1990) to 42% (2020) and are now larger than shrub/grasslands in good condition (35% 2020). This unprecedented landscape change poses significant challenges for restoration, threats from wildfire and loss of native species. We will present research that investigates the role of pre-emergent herbicides in cheatgrass management and determines effective seeding strategies to biologically control (suppress) cheatgrass in order to enhance the resource productivity and sustainability of arid rangeland ecosystems. Our research has found that pre-emergent herbicides, such as Imazapic, can decrease cheatgrass densities by 95+% while the herbicide remains active (about 1-year). This control depletes the cheatgrass seed bank and effectively reduces competition with seeded perennial grass species, which are required to develop a cheatgrass resistant plant community. We will present data on the probability of establishing native perennial grasses as well as introduced rehabilitation species such as Siberian wheatgrass (Agropyron fragile) and forage kochia (Bassia prostrata). Our research demonstrates the tools and effective strategies to provide usable guidelines for stakeholders to rehabilitate cheatgrass dominated landscapes, to more productive, sustainable and fire resilient ecosystems.