Abstract
Globally, rangelands are being threatened by invasive annual grasses (IAGs) that alter fire regimes, drive vegetation type conversion, and alter ecosystem function. This study evaluates vegetation responses to an Imazapic treatment applied in 2020 to control a population of Taeniatherum caput-medusae, an IAG, that flourished following a severe wildfire in 2013. The site, located on a Bureau of Land Management (BLM) grazing allotment east of Klamath Falls, Oregon, has been monitored annually using the Assessment, Inventory, and Monitoring (AIM) protocol since the Summer of 2022. Over this period, very little T. caput-medusae has been detected while bare ground has declined, indicating an effective herbicide treatment and positive site recovery. Species richness has also increased along with total vegetation cover, specifically of native perennial grasses, indicating establishment of desired vegetation. However, increasing populations of invasive species like Bromus tectorum and Lactuca serriola indicate a potential secondary invasion that requires continued monitoring and management interventions. Targeted grazing, alternative herbicide options, and sagebrush plantings are all management tools that could support ongoing restoration of this sagebrush steppe ecosystem.
Date
Spring 2025
Department
Forestry, Fire, & Rangeland Management
Advisor/Professor
Dr. Kerry Byrne
Citation Style
APA 7th edition