Thistle epidemic... how to handle?

[Ken45101]

Spraying and/or regular mowing will do a lot to minimize thistle.

 

[RalphVa]

We had a caller into the extension office about these. According to our books, none of the do-not-kill-the-grass chemicals are very effective on them. So, I advised him to get a 2 liter plastic container, cut it horizontally in the middle. Put the spout over a hand pump sprayer nozzle (may have to remove the nozzle and screw it back on) and spot spray them when young with Roundup or glyphosate.

Do not overuse Roundup though. There's some evidence so far that shows a connection between it and increasing gluten intolerance.

Ralph

 

[mikehaugen]

Would tilling/discing/plowing before seeds be effective?

 

[jeff9366]

Yes, but.....there are three or four years worth of viable seeds in your soil, waiting to germinate when exposed to sunlight.

Weed eradication is a several year process.

 

[Redneck in training]

Yes, but.....there are three or four years worth of viable seeds in your soil, waiting to germinate when exposed to sunlight.

Weed eradication is a several year process.

Tell me about that. We have Prairie restoration process in progress. We are in fourth year getting rid of the weed and I think we will need one more before we will be able to seed it with prairie grasses.

 

[Mdejoode]

I paid my boys to dig them out for me. My only problem is now they left for college and don't plan to move back. Looks like I may start getting more exercise next summer.

 

[TomSeller]

Not to pop anyone's bubble but pulling the roots on a Canada Thistle is not what you might think. The roots are very deep and have lateral spreading roots. See stock pictures from Google searches. Cultivation can work, but since the roots re-sprout, you must stay after them to starve out the roots. Seed is proficient but viability is low when the seeds land on other crops but are very effective when they land on open soil. Locally they are likely to spread by the lateral roots, with seed for establishing new or distant areas of infestation. What is unclear to me is if herbicides like Roundup, which attacks the roots, can kill plants across the lateral roots. They did not become a noxious weed in as many states and countries as they have because they are easy to control.

 

[TomSeller]

We had a caller into the extension office about these. According to our books, none of the do-not-kill-the-grass chemicals are very effective on them. So, I advised him to get a 2 liter plastic container, cut it horizontally in the middle. Put the spout over a hand pump sprayer nozzle (may have to remove the nozzle and screw it back on) and spot spray them when young with Roundup or glyphosate.

Do not overuse Roundup though. There's some evidence so far that shows a connection between it and increasing gluten intolerance.

Ralph

Good idea, very clever. This would work well for a limited number of thistles. It is another story for infestations by the tens of thousands in large fields.

 

[mikehaugen]

this may seem like a dumb question, but thistle is an annual correct? If you were able to keep on top of it and kill the plants before they seeded, then you just have to worry about the seeds in the ground correct? My thoughts would be that keeping them mowed would be as effective as anything else then right? But will they seed at a height lower than a mower would get to?

 

[TomSeller]

this may seem like a dumb question, but thistle is an annual correct? If you were able to keep on top of it and kill the plants before they seeded, then you just have to worry about the seeds in the ground correct? My thoughts would be that keeping them mowed would be as effective as anything else then right? But will they seed at a height lower than a mower would get to?

Depends on the thistle. Canada thistle is perennial.