An analysis of how spotted knapweed takes over rangeland suggests that sustainable weed management will need to focus on establishing and maintaining diverse desirable plant communities, rather than simply killing weeds. As noxious weeds invade rangeland, most people notice a difference in the number and amount of native plants.
Idaho fescue is a very important perennial grass in many rangeland ecosystems.
The study also showed many other species decrease as knapweed increases. There is one reason among the many reasons that can give us a hint about how to reduce knapweed. Yes, knapweed has high seed production and is very competitive. Most wildlife and livestock won't graze it, and it lacks natural enemies in this part of the world. Another study by the rangeland weed group at MSU in 1997 gave us an important clue.