Guide to Exotic Thistles of Montana

5333A new publication from Montana State University Extension is designed to help identify invasive exotic thistles and verify those that are native to Montana. Five exotic thistles and ten native thistles grow in Montana.

People often think that the only good thistle is a dead thistle. While this can be true for well-known invasive exotic thistles like Canada or musk thistle, some thistles are Montana natives and better off alive than dead due to their beautiful flowers and foliage and the habitat they provide for wildlife.

The free publication includes a tutorial of how to use a simplified key and a brief description of the important anatomical features and terms that are needed to successfully identify the thistle. Order Online. If you have questions, please call the MSU Extension Distribution Center at (406) 994-3273 or email