Spotted Knapweed

I remember seeing the Spotted Knapweed (Centaurea maculosa)  when I was a youngster, either here or in California, and it was one of my favorites then and still is now. Of course, with a name that includes "weed" in it, my admiration is now filtered somewhat! But after reading up on it, I have a new appreciation for its place in the world! Its name comes from the spots that are seen on the bracts in the center.

The Spotted Knapweed is a European native and is considered invasive in much of North America. One source indicated that it arrived to the Northwest in a ship's ballast. The Oregon Department of Agriculture calls it noxious and claims it has caused $50 million or more in lost revenue. Dang, it's hard to admire a flower like that!

What I found fascinating about this knapweed, is that it is classified as a "Pioneer Species." I had not heard this term before, but means the plant can spread rapidly and dominate disturbed areas by its ability to gather moisture quickly, by its prolific seed production, and some believe it produces a natural herbicide (catechin) that limits growth of other plants. Unfortunately, most native plants are unable to compete with this trifecta.

In Montana and Northern Idaho, the Spotted Knapweed covers acres of land, making for beautiful views and photo ops. Because it quickly forces out native plants, biological steps have been taken to control it in those areas.

We found these knapweeds growing near Farmington View School on Highway 219. (8/07/2013)

Spotted Knapweed with Queen Anne's Lace

Note the "spots" in center.

They love roadside disturbed areas.