By Morgan Graham
Hey everyone, 'tis the season for knocking back patches of thistle!
Following tips from Teton County Weed and Pest District and Bridger-Teton National Forest, Teton Conservation District staff members Emily Smith and Morgan Graham recently removed over 125 lbs. of thistle seed heads in the vicinity of the Munger Mountain and Game Creek trailheads! We intend to revisit these sites in future years to track our mechanical control progress.
Thistles are tricky and can come back even after being sprayed or pulled. If a thistle looks dead or drooped, but you still see a purple seed head, the thistle has succeeded in expanding its footprint.
If you want to get out there and be a native habitat hero, here are a few tips on treating thistles:
Pop and BAG the seed heads/flowers. Sometimes thistles will trick you and put out seeds after they’ve been sprayed or pulled (check out our IG stories). Make sure to bag the flowers/seed heads and put them in the trash, not on the ground.
Rip out the plant and let it compost in the field. You don’t have to bag the whole plant – just the seed head.
When treating thistles or other weeds with herbicide, check with Teton County Weed and Pest about the appropriate herbicide and correct concentration. Over-application of herbicide can negatively impact native vegetation. It is not uncommon to observe "scorched earth" where the incorrect amount or concentration of herbicide has been sprayed. These bare patches of ground can inadvertently provide a clean slate for rapidly establishing invasives like musk thistle and houndstongue to reseed and prosper without competition from slower growing native vegetation.
Also, shout out to Chris Owen with Friends of Pathways for helping us truck out all the seed heads we collected! Thank you!
Top photo by Penny Mayes / Musk thistle (Carduus nutans) / CC BY-SA 2.0