Knowledgebase

Thistles #762969

Asked July 21, 2021, 10:31 AM EDT

We have a vacation property on Riverside drive AKA Raymond. I have noticed a large amount of thistles (not sure of the variety) in our area by the road. I have also noticed a few here and there on our own property. I grew up on a farm in a neighboring state and was trained to get rid of them as quickly as possible. However, I have heard that some varieties are beneficial to pollinators and birds. Should I go with my instinct to attack them with a spade or leave them be? Thanks, Matt Rinne

Boulder County Colorado

Expert Response

Hi, Matthew,  Here is a recent article in the Boulder Daily Camera which talks about beneficial thistles:  https://www.dailycamera.com/2021/06/08/sharon-bokan-thistles-the-good-the-bad-and-the-native/
This may help you to determine if the thistles in your area are of a beneficial variety.

Here is a CSU Fact Sheet on another non-native thistle:  https://extension.colostate.edu/topic-areas/natural-resources/musk-thistle-3-102/
Musk thistle is a biennial weed that reproduces only from seed. The key to successful musk thistle control is to prevent seed production. Apply herbicides such as Tordon, Vanquish/Clarity or 2,4-D to musk thistle rosettes in spring or fall. Apply Ally or Telar up to the early flower growth stage. Combine control methods into a management system for best results.
extension.colostate.edu
So the Daily Camera article talks about 20 native species thistle that can be beneficial.  Hopefully you will be able to identify which category the species of thistle you have.
Boulder County Master Gardener
From: Ask Extension <<personal data hidden>>
Sent: Wednesday, July 21, 2021 8:35 AM
To: Boulder County Parks Master Gardeners <<personal data hidden>>
Subject: [EXTERNAL] Question assigned to you (#0032900)
 

Hi Boulder County,

Question #0032900 has been assigned to you by CSU E.

Thistles

We have a vacation property on Riverside drive AKA Raymond. I have noticed a large amount of thistles (not sure of the variety) in our area by the road. I have also noticed a few here and there on our own property. I grew up on a farm in a neighboring state and was trained to get rid of them as quickly as possible. However, I have heard that some varieties are beneficial to pollinators and birds. Should I go with my instinct to attack them with a spade or leave them be? Thanks, Matt Rinne

From: Matthew Rinne
Submitted: 07/21/2021 10:31 AM


To view/respond to the question, please login.

Please join the Ask Extension Experts group in Connect Extension. We will use that group to post updates about Ask Extension.
This message was sent by Ask Extension. If you need help, please visit https://askhelp.extension.org/.

An Ask Extension Expert Replied July 21, 2021, 11:55 AM EDT

Loading ...