We were driving along a beautiful grassy hillside covered in wildflowers when my wife pointed to one large bloom and said how sad it was that knapweed had invaded the field.
We should have stopped to look at the flowers more closely because I said, “Nope, those are thistles.”
Now that I’ve looked up thistles native to Montana and knapweed, I see they can look pretty similar. The ones we saw were unusual though because they had really dark purple flowers, instead of the more pinkish tone of most thistles and knapweed.
Knapweed is a much-hated weed in the West. It can grow up to 4 feet tall and is often found where the soil has been disturbed, like along roads. Thistles that are not native to Montana share a love for disturbed soil, as well, including the bull thistle, the musk thistle and the Canadian thistle.
Thistles are actually members of the daisy family, but they have those spikey leaves and spiny stalks that make them much less popular. Thistles native to Montana include the meadow or elk thistle, the prairie thistle and the clustered thistle. Native thistles tend to be found where the soil hasn’t been disturbed.
Here are some unusual thistle facts for you: A purple thistle has been the floral emblem of Scotland, a country in Europe, since the 1200s. In the 1500s the king of Scotland created the “order of the thistle,” kind of like a club for him and his knights. The order’s motto is: “No one harms me without punishment.”
If you want to learn more about thistles, or how to identify natives from nonnatives, Montana State University has a great pamphlet called the “Guide to exotic thistles of Montana.” The guide can also be found online.
— Brett French, Billings Gazette