I found a pretty flower...

Common teasel is a designated noxious weed in
Lake county, MT, and is a taprooted biennial that
can grow to six feet tall with spiny heads.  

Kari Lewis, MSU Extension - Glacier County

A couple weeks ago I was visiting with a client who said that while over on the West side of the mountains, he and his wife had come across a unique looking flower.  I was unable to provide an identification of the plant with his over the phone description, so asked him to e-mail me a picture.

A few days later, I received a couple pictures of the flower in my inbox.  It was tall, spiny, and had a purple flowerhead that I wasn’t familiar with (and no, it was definitely not knapweed, I’ve seen plenty of that!)  The client had found the plant near Ronan, noted it was very plentiful over there, and was interested in using the plant in dried flower arrangements due to its unique appearance.  Because I wasn’t personally familiar with the plant, I forwarded the pictures onto the MSU Extension agent in Lake County, who within a few minutes responded that the plant in question was Common Teasel, which is a designated noxious weed in Lake County.  Teasel is a stout, taprooted biennial which grows to 6 feet tall, and produces spiny heads often reaching over two inches with purple flowers protected by spine-like bractlets.  The plant is a native to Europe, and is now widespread as a weed in North America.

I thought this was a very teachable moment for a few reasons. 

First, the clients had participated in my Level 1 and Level 2 Master Gardener classes, where we discussed Integrated Pest Management and how critical it is to properly identify plants in order to correctly manage them.  Further, we discussed the danger of horticulturists transporting ‘pretty flowers’ as that is how most weeds are established.  I was proud that rather than simply bringing the plant home to Glacier county and potentially establishing it here, my Master Gardener students chose to seek out an identification of the plant. 

Secondly, even though I was not able to identify the teasel myself, I was able to quickly get an answer through the MSU Extension network.  Since common teasel is a Lake County noxious weed, it should be not moved across county lines, and I was able to quickly let my client know that this plant should NOT be brought back to Glacier county.

Lastly, I think this serves as a good reminder that if you come across a plant that you are unfamiliar with, please be sure to get proper identification before making plans to use it.  This is not an isolated incident, as occasionally we see weeds in flower beds that were originally introduced as flowers.  I also remember the story of one well-meaning church harvest dinner decorating committee that planned to use some fall like décor in the table arrangements, until someone pointed out that their planned décor was actually a weed and should not be transported to the church harvest dinner!

Your local MSU Extension office is a great resource for plant identification, and we really appreciate diligent clients who serve as ‘first responders’ from the field, noting if there’s new weed infestations we should be aware of, or checking before they add an unknown plant to a flower arrangement.