THE ISSUE: Quackgrass
Quackgrass (Elymus repens), is an aggressive cool-season perennial grass native to Eurasia; that invades pastures, lawns, ditches, crop-land, and other grassy areas. Quackgrass can be used as a forage for livestock, but its yield and feed quality are not as high as other grasses. Its extreme ability to spread and overpower other plant communities makes this weed dangerous.
Quackgrass has flat dark green leaves that usually have a small constriction towards the tip. It has clasping auricles (small projections that clasp the stem where the leaf blade meets the stem). Its rhizomes (underground stems) are its greatest offensive tool. A small insignificant patch of Quackgrass uses rhizomes to quickly spread, overtaking vast areas.
Integrated Pest Management (IPM) Options:
• Prevention— Learn to identify this plant. Never transport unknown plant material. Always clean tillage equipment before moving to new areas. Always plant clean seed!
• Mechanical—Tillage practices are not usually recommended, as it aids in the spread of this rhizomatous weed.
• Cultural— Maintain a healthy plant community by adopting practices that favor desirable plants.
• Chemical— Glyphosate is a good option in fallow situations or after harvest. Glyphosate is non-selective herbicide, do not apply to desirable vegetation. Visit https://pnwhandbooks.org/weed and search “Quackgrass” for more chemical control options. Always read and follow herbicide label directions.
Combine Management Options
Clean equipment when moving fields or when leaving infested areas. Plant clean seed. Only use tillage in conjunction with other control methods. Plant and maintain healthy plant communities by implementing cultural practices that favor desirable species. Use chemical control options when appropriate.
Justin Hatch, University of Idaho Extension Agriculture Educator in Caribou County. 208-547-3205 JLHatch@uidaho.edu