Great Basin Rangelands Research Unit, USDA, Agricultural Research Service: Assessing the efficacy of integrated cheatgrass management tools

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

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 2/14/2023
Publication Date: 9/2/2023
Citation: Harmon, D.N., Clements, D.D. 2023. Great Basin Rangelands Research Unit, USDA, Agricultural Research Service: Assessing the efficacy of integrated cheatgrass management tools. Meeting Abstract. 23:3.

Interpretive Summary: The greatest threat to the sustainability of ecosystem agricultural goods and services in the Great Basin is exotic and invasive annual grasses and associated fuels that increase wildfire threats. By understanding the ecology of exotic invasive annual grasses, such as cheatgrass (Bromus tectorum), tools and strategies for restoring degraded rangelands can be evaluated for effectiveness. Conducting replicated (site and year) field research efforts for each aspect of an integrated pest management plan (IPM) can provide critical data for quantifying the impacts of a conservation management practices. We will present a synthesis of two decades of research focusing on weed control (herbicide and mechanical), plant material testing (seeding efforts), competitive weed exclusion (cheatgrass and fuels suppression) and plant-soil relationships (soil moisture and nitrogen). Recommendations based on research results for application timing, seeded species selections and seeding rates as well as appropriate herbicide application will be reviewed. By studying the mechanisms that effect the outcome at each phase of a cheatgrass management plan, we can predict the likeliness of a successful conservation effort. For example, knowing that effective cheatgrass control can nearly double soil moisture (5% vs. 9%) and increase available nitrogen significantly (4 ppm NO3- vs. 56 ppm NO3- ) can emphasize the importance of pre-emergent herbicide applications prior to restoration seeding efforts. Through data analysis we have developed land management strategies that address cheatgrass impacts on the economic viability of livestock operations in the Great Basin and can provide guidelines for mitigating invasions as well as wildlife habitat loss. We will present a customer “friendly” means to decrease cheatgrass and wildfire frequency and increase natural resources in an effort to improve sustainable grazing practices and improve wildlife habitats.

Technical Abstract: The greatest threat to the sustainability of ecosystem agricultural goods and services in the Great Basin is exotic and invasive annual grasses and associated fuels that increase wildfire threats. By understanding the ecology of exotic invasive annual grasses, such as cheatgrass (Bromus tectorum), tools and strategies for restoring degraded rangelands can be evaluated for effectiveness. Conducting replicated (site and year) field research efforts for each aspect of an integrated pest management plan (IPM) can provide critical data for quantifying the impacts of a conservation management practices. We will present a synthesis of two decades of research focusing on weed control (herbicide and mechanical), plant material testing (seeding efforts), competitive weed exclusion (cheatgrass and fuels suppression) and plant-soil relationships (soil moisture and nitrogen). Recommendations based on research results for application timing, seeded species selections and seeding rates as well as appropriate herbicide application will be reviewed. By studying the mechanisms that effect the outcome at each phase of a cheatgrass management plan, we can predict the likeliness of a successful conservation effort. For example, knowing that effective cheatgrass control can nearly double soil moisture (5% vs. 9%) and increase available nitrogen significantly (4 ppm NO3- vs. 56 ppm NO3- ) can emphasize the importance of pre-emergent herbicide applications prior to restoration seeding efforts. Through data analysis we have developed land management strategies that address cheatgrass impacts on the economic viability of livestock operations in the Great Basin and can provide guidelines for mitigating invasions as well as wildlife habitat loss. We will present a customer “friendly” means to decrease cheatgrass and wildfire frequency and increase natural resources in an effort to improve sustainable grazing practices and improve wildlife habitats.