Thistle Management

[LarryBud]

Hi Folks,

I'm located in West Missouri. I'm converting 4 fields ( 18 acres total ) to Pollinator / Monarch Habitat through the USDA CSP program.

One Field needed dozer work to reshape some berms around the pond and to repair terraces likely installed many decades past This field is about 6 acres. Aprox 2 of the 6 were graded by the dozer. The remainder was chemically burned last fall, then, physically burned in January and broadcast seeded to pollinator in February. Unfortunately, we've had an extremely dry spring. Some rain in early March and nothing until last week.

Wherever the soil was disturbed, I have thistles and lots of them. I have a wide variety.... tall, short, wide, thin, dark green, light green. You get the idea. At least a dozen different thistles. I've been trying to spot spray with glypho but it's a losing battle. Of course, if any of my plantings are up, they go down with the thistle via glypho.

Suggestion? Next steps? I'm in the battle now as last weeks rain has super charged them and they are rapidly heading out. Not sure what to do.

 

[356]

LarryBud, greetings from NW Missouri. When I did my EQIP Pollinator/Monarch project, I had almost the same issue. After two chemicals treatments and a growing season burn, I drilled into the disturbed area. While it looks like a disaster IMO, my conservation agent wants me to continue to follow the plan, which will include a 2024 growing season burn. Even with the thistles and other invasives that were in the soil bank, the plots are supporting pollinators. Deer and turkey sightings are up significantly.

A growing season burn sounds like what you will need. Given $ have passed hands, you need to work with your agent on any modifications, or at least that is how my agreement worked. My contract does allow spot treatments, which I do using triclopyr. I don’t feel gly is the right herbicide for your needs. A day with a sprayer and triclopyr may be a good starting point.

Depending on where you are, feel free to PM me…I travel the I-49 route each month and would be happy to connect.

 

[b116757]

Maybe use a more selective herbicide also but still spot spray the thistles not broadcast spray the entire field perhaps Milestone would work but it will kill other broad leaf species so care should be taken.

 

[SD51555]

It's been a while since I've posted my thistle quackery, so here's the short version:

I'd let them run wild. Thistles are auto-toxic, meaning they will not grow again where they had just previously grown. This may take 2-3 years to complete itself, and most people's time horizons aren't that long. If they do keep coming back, I'd say you've got some severe soil issues that need to be addressed because your soil cannot evolve past the disruption of the dozer.

Thistles aren't all bad. You're going to have a seed bank full of thistle seed for the rest of time even if you hand remove every one right now. It was there before you started, and the seed will be there long after. Thistle is an iodine accumulator, breaks up compaction with it's big roots, feeds all sorts of beneficial bugs above and below ground, and goldfinch use them for food as well.

If they weren't there before you moved dirt, you'll probably evolve back out of them. I've turned up many thistle patches on my place (burns, sprayings, earth moving), and they have all rectified themselves after a couple growing seasons, and vanish until they are called up again.

 

[Angus 1895]

I have been told that in the fall, the thistle pulls fluid from the leaves to the roots.

this enhances herbicides activity on thistle.

mowing before the thistle flowers is another control option.

IMO letting a noxious weed “ run its course “ is not legal ,nor very neighborly.

 

[Native Hunter]

I have been told that in the fall, the thistle pulls fluid from the leaves to the roots.

this enhances herbicides activity on thistle.

mowing before the thistle flowers is another control option.

IMO letting a noxious weed “ run its course “ is not legal ,nor very neighborly.

I'm now only bothered by one thistle (Cirsium discolor) in my native prairie, and it is a tough one to deal with. The other thistles I had were easy to eradicate, but this one is a booger. That's because some of them germinate so late and make seed so late in the season. I do two things that keep them under control, but these things don't completely eliminate them.

First, after spring mowing, I will drive through the fields over the next few weeks and spray any that I see with 24D. That helps, but by the time the fields are getting tall and I can't drive anymore, there will be more thistles germinate or bolt from small ones that I missed.

Second, in the fall before deer season, I will do my annual mowing of shooting lanes. From my high perspective in the cab tractor, I can see pretty well, and the surviving thistles are tall by that time. However, their seed have not become viable. Hence, if I see any I will just swing over and mow them down.

Oddly enough, Cirsium discolor is a native thistle. All of the well know invasive, non native thistles (such as Canadian and Bull) are not a problem for me. I had a few Canadians, but when they raised up those big red heads early in the spring, I put on my ninja suit and attacked!

 

[H20fwler]

It's been a while since I've posted my thistle quackery, so here's the short version:

I'd let them run wild. Thistles are auto-toxic, meaning they will not grow again where they had just previously grown. This may take 2-3 years to complete itself, and most people's time horizons aren't that long. If they do keep coming back, I'd say you've got some severe soil issues that need to be addressed because your soil cannot evolve past the disruption of the dozer.

Thistles aren't all bad. You're going to have a seed bank full of thistle seed for the rest of time even if you hand remove every one right now. It was there before you started, and the seed will be there long after. Thistle is an iodine accumulator, breaks up compaction with it's big roots, feeds all sorts of beneficial bugs above and below ground, and goldfinch use them for food as well.

If they weren't there before you moved dirt, you'll probably evolve back out of them. I've turned up many thistle patches on my place (burns, sprayings, earth moving), and they have all rectified themselves after a couple growing seasons, and vanish until they are called up again.

I mostly agree with this, there is a reason the thistles thrive for awhile in certain areas. Eventually they seem to usually go away and other natives take over. Birds like goldfinches sure love them...so do bees.

To the original poster, if they bother you hit them with crossbow. Be carefull it will knock out all broadleaf plants it hits including trees. Then plant your foodplot, grass, polinators or whatever you are doing a few days after.