Thistle epidemic... how to handle?

[AchingBack]

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?

Some thistles are annuals, biennials, and as TomSeller displayed, the dreaded Canada thistle; which regenerates from the smallest of broken root pieces.

I've had the most success by beheading plants as soon as I see them emerge. My favorite tool for this is a 3" trenching shovel with a 'V' shaped notch I cut into it. I keep the notch, and the sides of the shovel sharpened. The small profile of the trenching shovel makes it easier to penetrate the soil than a regular spade. For maximum effect, I go as deep as I can in order to cut of as much of the root as I can. Then I pull them, and they go into the burn barrel. Persistence is key. You can't turn your back on nasty weeds. Just when you think you killed them all, think again.

It took me over thirty years before I considered my seven acres of star thistle as under control. The only ones I allow to remain standing are the ones with a healthy star thistle beetle population.

 

[woodlandfarms]

We use Crossbow for our thistles.

But this is something I learned this year from the MIL and you won't be happy. When you spray the thistle, it will bloom if it can. All the engergy goes to creating seeds, and yes, if you bump those heads you just add to your misery next year. Anyway, the long and the short of it is that I sprayed a 100 foot embankment, then a week later went through and cut the heads of the thistle off. I was told to leave the body until it was brown and dead, as the most chemicals would get into the extensive root system.

We will see how the berm looks next year.

 

[TomSeller]

We use Crossbow for our thistles.
..... I was told to leave the body until it was brown and dead, as the most chemicals would get into the extensive root system.
.

That is the tough part, seeing the thistles still bloom. Do you understand the seeds to still be viable? They say a few weeks and the herbicide is into the roots at which time I mowed this year. We will see next year.

 

[bcp]

In my experience, the only sure, immediate, and permanent thistle solution comes in these trucks.



Bruce

 

[mikehaugen]

In my experience, the only sure, immediate, and permanent thistle solution comes in these trucks.



Bruce

<img src="http://www.tractorbynet.com/forums/attachment.php?attachmentid=340608"/>

At least until it cracks

 

[forgeblast]

Simple perennials reproduce only by seed production and emerge from the same vegetative structure every year. Dandelion is an example of a simple perennial (Table 1). Creeping perennials often reproduce by both vegetative structures and seed production. Canada thistle is an example of a creeping perennial (Table 1). Finally, woody perennials may be either simple or creeping, but they also produce secondary growth or a woody structure that enables them to become very large and usually aggressive. Multiflora rose is an example of a woody perennial that is also creeping (Table 1).
Weed Management in CREP Grasslands — Weed Management — Penn State Extension

Table 2. Effect of some foliar applied herbicides on selected weed species possibly found in CREP areas Herbicide/ Weed Species Life Cycle 2,4-D Banvel/ Clarity 2,4-D + Dicamba Cimarron Plus Cimarron Plus + Dicamba or 2,4-D Crossbow

A = annual; B = biennial; P = perennial

Weed control: 10 = 95–100 percent; 9 = 85–95 percent; 8 = 75–85 percent; 7 = 65–75 percent; 6 = 55–65 percent; N = less than 55 percent or no activity; — = no data available or unknown

Other herbicides such as MCPA, 2,4-DB, Buctril, Pursuit, Journey, Garlon, Curtail, Overdrive, and Outrider also can be used on CREP grasslands to control various kinds of weeds. Refer to the specific herbicide labels for additional details about each product. [Herbicide labels can be found online (e.g., Crop Data Management Systems, Inc. - Home, www.greenbook.net).]
Must Be Controlled in CREP Areas

Glyphosate ForeFront Milestone Redeem R&P Stinger Plateau (Post)
Marijuana A 8+ 8+ 8+ - - 8+
Canada thistle P 7+ 7+ 7+ 7+ 8+ 7+
Multiflora rose P 6 7 7 9 9 9
Johnsongrass P N N N N N N
Mile-a-minute A N 9 - - - 9
Kudzu P 6 7+ 8 8+ 8+ 8+
Bull thistle B 8+ 8+ 9 8+ 9 9
Musk thistle B 8+ 8+ 9 8+ 9 9
Shattercane A N N N N N N
Jimsonweed A 8 9 9 9 9 9
Purple loosestrife P 7 - - 8 8 8+
Giant hogweed B/P 7 7 8 - - 8
Goatstrue P 7+ 8+ 9 - 8 -
Should be Controlled in CREP Areas
Plumeless thistle B 8+ 8+ 9 8+ 9 9
Dandelion P 9 7 9 6 8 9
Honeysuckle spp. P 7 7 7+ 7+ 8 7
Spotted knapweed P 8+ 8+ 9 7+ 8+ 8+
Japanese knotweed P 7+ 7+ 8 6 7+ 7+
Autumn olive P 7+ 7+ 7+ 6 7+ 7+
Tree-of-heaven P 7+ 7 7+ 6 7 8
Japanese stiltgrass A N N N N N N
Horseweed A 8+ 8+ 9 7+ 8+ 8+
Not Necessary to Control in CREP Areas (Nuisance Weeds)
Field bindweed P 8 8+ 8+ 6 8 8
Burdock B 8+ 7+ 8+ 8 8 9
Bedstraw, smooth P 7 7 7 N 7 8+
Dock spp. P 7+ 7+ 9 8+ 9 8+
Horsenettle P 8 8+ 8+ 9 9 8
Poison ivy P 7+ 8 8+ 6 7 8+
Mugwort P 6 7+ 7+ 7+ 7+ 7+
Black locust P 7+ 7+ 8+ 7+ 8 8+
Dodder A 6 6 6 - - -
Table 2. Effect of some foliar applied herbicides on selected weed species possibly found in CREP areas (cont.) Herbicide/ Weed Species Glyphosate ForeFront Milestone Redeem R&P Stinger Plateau (Post)

A = annual; B = biennial; P = perennial

Weed control: 10 = 95–100 percent; 9 = 85–95 percent; 8 = 75–85 percent; 7 = 65–75 percent; 6 = 55–65 percent; N = less than 55 percent or no activity; — = no data available or unknown

Other herbicides such as MCPA, 2,4-DB, Buctril, Pursuit, Journey, Garlon, Curtail, Overdrive, and Outrider also can be used on CREP grasslands to control various kinds of weeds. Refer to the specific herbicide labels for additional details about each product. [Herbicide labels can be found online (e.g., Crop Data Management Systems, Inc. - Home, www.greenbook.net).]
Must Be Controlled in CREP Areas
Marijuana 9 8+ - - - -
Canada thistle 8+ 9 9 8+ 9 9
Multiflora rose 8 7 6 7+ 6 -
Johnsongrass 9 N N N N 6
Mile-a-minute 9 9 9 - N 9
Kudzu 8+ 8 8 8+ 8+ -
Bull thistle 9 9+ 9+ 9 9 8+
Musk thistle 9 9+ 9+ 9 9 8+
Shattercane 9 N N N N 7+
Jimsonweed 9 9 8 9 9 7
Purple loosestrife 8+ - - - - -
Giant hogweed 9 - - 8+ 8+ -
Goatstrue 7 7 - - - -
Should be Controlled by CREP Areas
Plumeless thistle 9 9+ 9+ 9 9 9
Dandelion 8 8+ 7 8+ 8 6
Honeysuckle spp. 7+ 7 6 6 N -
Spotted knapweed 8+ 9 9 9 9 -
Japanese knotweed 8 7 6 7+ 7+ -
Autumn olive 7+ 7+ 6 7+ 6 -
Tree-of-heaven 7+ 7 6 7+ 6 -
Japanese stiltgrass 9 N N N N 6
Horseweed 8+ 9 9 8+ 8 -
Not Necessary to Control in CREP Areas (Nuisance Weeds)
Field bindweed 8 7 N N N 6
Burdock 9 8 7+ 9 8+ -
Bedstraw, smooth 9 9 9 8+ N -
Dock spp. 8+ 8+ 8 8+ 8 6
Horsenettle 8 8+ 8+ 7+ 6 -
Poison ivy 7+ 7 - 8 6 -
Mugwort 7+ 6 - 8 8 -
Black locust 7+ 7 6 8+ 6 -
Dodder 9 - - - - -

Sorry for the large post but it had great info and provided what herbicides to use.

 

[TomSeller]

In my experience, the only sure, immediate, and permanent thistle solution comes in these trucks.
Bruce

Actually, Canada Thistle grows very well in Concrete.

 

[jeff9366]

Has anyone used Dupont Cimarron MAX for thistle control? Season long broadleaf weed control with one application claimed.

Check the link:

DuPont? Cimarron® Max herbicide controls broadleaf weeds

 

[TomSeller]

Has anyone used Dupont Cimarron MAX for thistle control? Season long broadleaf weed control with one application claimed.

Check the link:

DuPont? Cimarron® Max herbicide controls broadleaf weeds

I don't. Do you know what they mean by " season-long control"? Does it just yield top-kill?

 

[Ken]

Has anyone used Dupont Cimarron MAX for thistle control? Season long broadleaf weed control with one application claimed.

Check the link:

DuPont? Cimarron® Max herbicide controls broadleaf weeds

5 years ago had a tornado take down app. 30 acres of oak and pine. Destroyed to point no one wanted the trees. So hired a dozer to win row the trees and burned.
The next year every where the dozer had been was a carpet of Canadian thistles. 1st. year used a 250 gal tank sprayer and sprayed the field using a 2-4-D type spray. And every 2 weeks again went over the field spraying any plant seen. That year about 1000 gal. of plant spray. And every year since now only need a 25 gal sprayer mounted on tractor.
Each year any weed missed will start a fan of seed that grows. that is 50 foot long. And the plant stays green all winter so spring time it is the first to come to seed.
I have driven over the 30 acres so many times know almost where the weed will be already in seed .
The one advantage of being in the field so much. The deer now think I'm part of the lively hood in the field and don't go far from the tractor.
ken