Controlling Thistle

[SprigOfTheLivingDead]

So, it's getting into Autumn here in Minnesota. Leaves are falling, turkeys are running around and my neglected jalapeno, scotch bonnets and tomatoes are wilting. Soon enough the cold will come, snow will fly and then the season known as mud will begin again and with that will start the whole process of thistle growth, the bane of my prairie.

Who amoung you has faced off this scourge in a large area and won? I spent a good amount of time this early summer yanking it out of my land, but that still leaves acres of it to go. What methods or chemical have you used with success against this?

Once the plants started to flower I just went nuts with clippers and took the flowerheads off, but I still didn't come close to getting it all. That may have prevent some seeds from spreading, but the roots are still alive and well.

I also went thru some areas and just clipped the plants at soil level, hoping to starve them of light in the tall surrounding grass

 

[frustratedearthmother]

Wish I had an answer for you... My guess is it will take a multi-faceted approach. Not sure how much area you're dealing with - but as you already know, keeping it cut so it can't go to seed will probably help somewhat.

 

[Lazy Gardener]

Aside from the chemical means, which I refuse to use... Sounds like you are doing the best you can. Exactly how much land are they encroaching upon? What are you using that land for? Is this pasture land? Other weedy issues? Do you hay it? If you continually cut it before it can go to flower, you may eventually win. If this is pasture, it may be time to consider renewing it. Plow it,perhaps several times, then reseed it at a heavy rate with what ever pasture mix does well in your zone. You might want to contact your County Agricultural extension office, and seek advice for organic control. Your tax dollars are supporting this service. So, IMO... it's a good idea to call these folks and help them to earn their pay checks.

Canadian thistle spreads from seeds AND underground rhizomes/roots. Here's an article:

https://oregonstate.edu/dept/nursery-weeds/feature_articles/thistles/thistles.html

You are wise to destroy all blossoms as soon as you see them. When doing so, cut the plant at the base instead of just cutting the blooms. We have some thistle plants that show up in my lower lawn area. I go through, and dig the roots out as soon as things start to green up in the spring. If the crowns sprout again, I repeat the digging attacks. Close mowing will help to starve out the plants.

 

[Britesea]

You could try a Vinegar spray. It kills the top growth but not the roots, so you have to do it repeatedly. I've found that it is helping with my couch grass problems... but it will take several years before the plants finally give up the ghost. Still, it's a lot safer - and cheaper - than RoundUp

 

[Lazy Gardener]

Straight vinegar? 5%?

 

[Britesea]

Yep. If you add a squirt of dish detergent, like Palmolive, it'll make the vinegar stick better. What it does is dessicate the leaves so the top part of the plant dies. I've seen recipes that say to add epsom salts, but since that's a fertilizer, doesn't seem like a good idea when you're trying to kill the roots. I just go over the area about every 3-4 weeks and spray to get any new shoots coming up. This is the second year, and I am seeing a definite reduction in the couch grass. Can't let up though, or it'll come back.

 

[Lazy Gardener]

When they use epsom salt in a weed killer formulation, it is used at much higher concentration. However, given the expense of it, I prefer to use it as a fertilizer!

 

[Beekissed]

http://greyduckgarlic.com/women-vs-weeds.html

 

[SprigOfTheLivingDead]

Wish I had an answer for you... My guess is it will take a multi-faceted approach. Not sure how much area you're dealing with - but as you already know, keeping it cut so it can't go to seed will probably help somewhat.

Multiple acres. I'll also add the imgredient that I have 5 young kids and an on the property tree farm, so time is always lovely

 

[Hinotori]

I cut them down to only a few inches and use one of the step in weed removers. It works for the 2 types of thistles we have here. Works even better if I catch them when they are small.

One of these things.
https://www.amazon.com/dp/B004S0PH1A/ref=cm_sw_r_cp_apa_i_OCHDDbNHJEQPD