Invasive grass known as medusahead discovered in Montana
Also known as medusahead wildrye, the invasive plant was discovered in mid-November by Bryce Christiaens, weed coordinator for Missoula County. Chistiaens then sent a sample of the plant to MSU to verify the find.
Medusahead is listed as a noxious weed in California, Colorado, Nevada, Oregon and Utah. Like another troublesome annual grass, cheatgrass, medusahead initiates growth early in the growing season, reducing moisture for perennial grass species. Once it dominates a site, the land has limited value for livestock or wildlife. It is unpalatable based on the high silica content and the seed head contains stiff awns, or bristles, that can injure eyes and mouths of grazing animals.
MSU botanist Matt Lavin said he has seen plenty of medusahead in southwest Idaho in open range country even with no recent burn history, where it's common on southwest-facing rangeland and often grows alongside rush skeletonweed. While he has long suspected it occurs in Montana, this is the first time MSU has a physical sample to study.
Response efforts are underway, said Doug Dupuis, range specialist for the Confederated Salish and Kootenai Tribes.
"We're in the early stages of developing a plan and will work with Tribal specialists, counties, Montana State University and adjacent landowners to evaluate options and implement management to control and potentially eradicate this new invader," Dupuis said.
Dupuis said Partners for Regional Invasive Species Management, a program that has been addressing invasive weeds in Lake County and Sanders County on the National Bison Range, will be an invaluable tool as they move forward. Preliminary efforts will involve surveying the area to estimate the total area infested and drafting a long-term management strategy.
Jane Mangold, a rangeland weed specialist with MSU Extension and assistant professor in the Department of Land Resources and Environmental Sciences, said it is important to be aware of what this grass looks like so infestations can be detected and addressed when they are still small and manageable. Educational material will be developed to assist with identification and management of medusahead.