Have noxious weeds been spreading over the past 100 years?
Yes. They have been spreading at an alarming rate. For example, spotted knapweed arrived on the west coast in 1893 on the San Juan Islands in Washington. By 1920, this weed has established over 24 countries in three northwestern states, with several large infestations near Missoula, MT. Now, spotted knapweed is established in the western United States and has invaded all counties and about 5 million acres in Montana alone. Can noxious weeds cause the loss of wildlife habitat? Yes. Dense infestations of noxious weeds reduce wildlife forage, alter thermal and escape cover, change water flow and availability to wildlife, and may reduce territorial space necessary for wildlife survival. Areas dominated by leafy spurge receive less use by deer (3 times less use) and bison (4 times less use) compared with similar infested areas. Elk use increased about 4 times after controlling the dense spotted knapweed infestation on study sites. Can noxious weeds displace threatened and endangered species
Related Questions
- What are the risks of the introduction and/or spread of noxious weeds within the Last Chance treatment areas and what plans does the Forest Service have to combat noxious weeds?
- How do I know whether or not seed has been certified and tested for purity, germination, and noxious weeds?
- Have noxious weeds been spreading over the past 100 years?
