Invasive Species, Noxious Weeds & Aquatic Nuisance

Employee Spraying Noxious Weeds

There are 21 major species of noxious weeds (invasive) on the Black Hills National Forest in South Dakota and Wyoming. 


Noxious weeds are aggressive invaders of natural plant communities that reduce forage available for wildlife and livestock. 

Musk Thistle

Black Hills National Forest Weed Pictures

Noxious Weed Prevention Newsletters



Canada Thistle - Known Areas

Common Tansy - Known Areas

Houndstongue - Known Areas

Leafy Spurge - Known Areas

Musk Thistle - Known Areas

Other Species - Known Areas

Spotted Knapweed - Treated Areas

St. Johnswort - Known Areas

Wyoming Game & Fish Department - Aquatic Invasive Species (AIS) Program

  • AIS decals can be: 1) purchased on-line and at a number of sales locations throughout Wyoming (sports stores, country stores, mini-marts, K-Mart, --see list).
  • Note: Wyoming G/F does not have the abiity for the Forest Service to sell the AIS decals in the field. Customers must obtain their AIS decals either from online internet sale or iPOS automated license selling agent.

For further information, questions, or comments, contact Steve Hirtzel, Fisheries Biologist, at (605) 673-9200.!ut/p/z1/04_Sj9CPykssy0xPLMnMz0vMAfIjo8zijQwgwNHCwN_DI8zPyBcqYKAfjlVBmA9cQRQx-g1wAEci9eNREIXf-HD9KKxWIPuAkBkFuaGhEQaZjgCVqf1Y/dz/d5/L2dBISEvZ0FBIS9nQSEh/?position=SubFeature%2A&pname=Black%20Hills%20National%20Forest-%20Land%20&navtype=BROWSEBYSUBJECT&ss=110203&navid=130000000000000&ttype=detail&cid=STELPRDB5112187