Working together to strengthen and support noxious weed management efforts in Montana.

Targeted Grazing

Proper grazing utilization of native rangelands is vital to maintaining a healthy productive landscape; these native plant communities have evolved under grazing pressure for centuries from migratory herds of large grazing animals. Livestock use today is an important tool in maintaining healthy ecosystems, and they can be very effective in steep and rocky terrain. Controlled or strategic grazing by sheep, goats and/or cattle can be a highly effective weed management tools with precise application based on an understanding of plant-herbivore interactions. Effective grazing programs for weed control require a clear statement of the kind of grazing animal, timing, and rate of grazing necessary to reduce noxious plants and maintain healthy rangeland ecosystems. Using animals to graze is a high management option, as sheep and goats in particular need to be monitored closely to keep them within a targeted area. A successful grazing prescription should cause significant damage to the target plant, limit irreparable damage to the surrounding vegetation, and be integrated with other control methods as part of an overall weed management strategy. Sheep grazing is often the most economical and ecologically sound tool available to manage invasive plants such as established patches of leafy spurge. Sheep will not graze an area uniformly; consequently, a method should be employed to concentrate activities in a specific area. The primary function of a grazing management program is to halt seed production. Other multifaceted approaches should be integrated as well. Although sheep grazing will reduce density and biomass of noxious weeds, eradication does not occur.

Noxious weeds it works for: leafy spurge, spotted knapweed, Dalmatian toadflax, and Canada thistle. Animals have to graze the noxious weeds before seeds mature in order for this method to be successful. For more information on targeted grazing, please contact Lisa Surber or Rodney Kott of the MSU Sheep Institute at or