Control Thistle in Pasture

[GreenValley]

Usually mow Canada thistle in pasture but it won't kill. It has to mow every year. wonder any one successful control thistle in pasture, I like to hear how to control thistle in pasture

[countryguy]

One thing I am going to do when I can find the darned time is pull out the weed wiper and givem a shot.Being as the thistles are the only thing left standing tall at this time of year it will work great.Maybe this is an option for you?

[grassfarmer]

Compaction is the best killer of thistles I've seen - if we have a small patch needing controlled we haul the mineral feeder into the middle of it. Once the cows obliterate it with feet marks it won't grow back again.
More spread out thistles in the pasture can be controlled by intensive grazing, our cows will happily eat at least the top of the thistles if they are at the lush green stage of growth. It has been proven that they are perfectly good feed if your cows eat them under these conditions. Expecting them to eat old, tall thistles once they are the only thing remaining in the pasture won't work no matter how much you starve your cows. Anyone who has thistles standing tall in bare pastures now is managing their pastures in a way that will ensure the thistles thrive and spread. Management is the problem, thistles the symptom.

[countryguy]

Normally Grassfarmer I would agree with you but this year the problem is drought.You can convince yourself all you want that everything is a "management" problem but i'd sure like to see you "manage" in a year with less than 3 inches of rain all year.Some things are just beyond our control.

[cswilson]

We actually controlled a bad thistle patch by accidant in the last drought-lost the water in one pasture so gave it a year off-the thistle was almost gone the next year. Turn some horse4s out in a thistle patch in a rain storm and they will kill alot of it. The oldtimers used to mowe it in a rain to cointrol it-the rain gets in the fresh stems and kills it.

[Horse]

Thistles cut them in may they will be back the next day cut them in june they will be back soom cut them in july and they will die.
Where I have problems is with the dry weather and the wet spots drying back and the thistle follow the wet line back where treating them is imposible, if you want chem control I have had very good luck with Curtail M .

[GreenValley]

I agree cswilson, mow thistle when rain go through inside stem make it rot and kill thistle. Once time I has bad thistle patch about 4 feet tall with heavy density, mow them, year later, it still but not as heavy density as it was, but it lessen density. Also old timer say best time mow is New Moon on August. I have try that method but it lessen density. Other time I try spray with Lontrol when thistle is about 3 inch to before rosette flower on pasture, result is spray do kill but next year they are come back. Lontrol itself do not kill effective. As I do experiment on this before doing spend lot money on all pasture with no effective. I have try roundup spray on heavy patch along ditch and do this apply each year for 2 years, it might gone as I have patch that was thistle before, it doesn't come back. But not on pasture, the pasture is more difficult to kill than ditch. Funny.
I has 1 quarter of land, about half of quarter now fill with thistle, wonder if worth money to spend on Lontrol alone might help. Or any else would help. I am been stuck with thistle.

[exnaboe]

I have been down the same road. Roundup seemed to have done a good job - but the thistles were back the following year. Again Lontrel looked good, and did eliminate some of the thistles, but it was ineffective the next year for some reason. Last year I sprayed with Grazon, which seems to have done a good job, on thistles as well as other weeds like tall buttercup and yarrow. I have just sprayed an area near our creek- where I can't use Grazon, with Restore, and will see how that works out.

[sagewood]

I used Grazon in a reclaimed gravel pit area two years ago and it still seems to have good effect. I sure can see the few spots where the sprayer missed, but otherwise the Grazon seems to have controlled buck brush, wormwood and the nasty thistle. This year seems to be a good growing year for thistle, at least in this area. I have never seen so many prolific thistles in slough land and in the ditches...the rain came at the right time for them and then the extreme heat in late June just helped them along. With all the seed that is set on them now, I expect we will enjoy them for years to come.

[cowman]

Thistle is a survivor...without a doubt.
GrazeOn is probably the most bang for your buck right now.
Restore looks good but not sure if the economics are there...except under environomental concerns?
Big Bang theory: Tordon 22k? Five year control...and yep it is actually pretty close to that! The problem....$45/acre! Maybe over five years not that bad? It personally is my favorite herbicide.
Lately I'm coming around to the theory Lontrel at the heavier rates might be a viable option(with added environmental concerns) but it is not cheap! Milestone also looks promising.
I think the important thing to consider is how much moisture/nutrients does Canada thistle rob you of? And also what is the best time to spray? My opinion(for whatever it is worth?) is NOW! After the thistle has basically reproduced, it starts to try to survive? After all it is a true perennial? Done seeding it is taking in nutrients to tide it over until next year. What better time to give it a good shot of picloram(22K)? The amount of viable seed is actually quite small in relation to amount of "fluff" produced? And guess what is waiting in the soil when little thistle seedlings start to grow?...picloram.
Now I know this attitude won't sit well with the "back to nature crowd"...but the fact is we have this technology and if we don't use it, then how smart are we? Whatever puts a dollar in your pocket...is my own personal opinion? Tordon 22K is probably the most environmentaly safe product on the market today in terms of mammalian health.(Exception..Milestone might be even safer!)
Just my opinion.

[cswilson]

The funny thing is some of us 'back to nature' guys have brought thistle troubles under control while the chem junkies just keeping writing cheques for the next great bomb to drop on it. How smart are they-something to think about.

[Smithy]

I have had some success with spraying salt water on thistle in and around my sheep pen in the spring. It trains the goats and sheep to eat it. I withdraw their minerals for a few days and then spray and they attack it for the salt. It doesn't work if it gets too far ahead and it doesn't work with the cows.

[mhittinger]

There will be a demonstration/workshop near Athabasca on Thursday Aug. 31. This event will hilight training livestock to eat weeds like Canada Thistle and Tansy, two very tough weeds to kill. Molasses is a great tool to use for this, and a feed analysis on Tansy reveals 21.5% protein and 65% TDN. The thing about Tansy causing abortions is also a myth. If you are interested in attending, please call Mike or Vicky at (780) 939-8374. Leave a message.

[mjohn]

Just to clarify. In Alberta we usually refer to Tanacetum vulgare as 'Tansy'. Other provinces may be refering to Sencio jacobaea or 'Tansy Ragwort'. They look a little similar, but Sencio flowers have petals while the Tanacetum flowers are just little yellow 'buttons.

The reason I make the distinction is that 'Tansy Ragwort' is fairly toxic and livestock poisonings are common. The poisonous compounds in the Tansy Ragwort are called alkaloids. This type of toxin usually causes irreversible liver damage. It is also possible that these types of alkaloids are fairly carcinogenic.

Common Tansy (Tanacetum vulgare) also contains several phytochemicals that could cause problems. The abortion concern isn't really a myth, but the amount consumed would have to be substantially high to cause problems. The compounds of concern are terpenes and terpenoids such as Thujone. Thujone is a fairly well known drug and a liquer made from Absinthe is known to contain it. Rumor has it that a famous painter was soused on it when he cut off his ear, but then it was also rumored that he sometimes ate his paint. At any rate, these compounds can have side effects and are considered teratogenic in that they could cause birth defects or abortions.

In the case of Tansy, the amount consumed must be fairly high, or we would see more problems with it than we do. One real interesting aside is that these same compounds may also have some benefits. Some research on wormwood (absinthe) containing thujone, has indicated that it could have limmited insect repellent and anthelmintic ('de-wormer')activity. It is kind of intriguing that they are rediscovering the effects of some of the old folk medicines.

Controlling tansy and thistle without having to resort to herbicide is a good tool for us to have. Training cattle to eat weeds is a great idea! My point would be that the operative word is 'training' not 'forcing'. I have no idea how much tansy a cow would have to eat before problems would occur, but it is likely a lot. If she has been trained to eat it and balances her consumption with decent grass then there should be no worries.

[cakadu]

Weed inspector told me many years ago that if you mow the thistles and it rains hard, they will essentially drown, or rot. This year we didn't have to mow - that bad hailstorm did the job for us. Then the additional inch of rain we got the day after that helped them on their way to drowning.

The sheep will take the buds off and prevent them going to seed. They are the best weed control that we have.

The question that I have about chemical treatment relates to whether you are treating the problem, or a symptom? If you have to go towards stronger and stronger applications, or moving to different chemicals to do the job, then are you really treating the problem? If you don't change grazing practices etc., then won't you continually be treating the symptoms?

Nature abhors a vaccuum and the weeds grow because they can. We are slowly eradicating our problem, but again, it came because we rented the pasture out to someone who swore he wasn't going to overgraze and guess what happened? We are left to deal with the problem.

It seems to me that if you continually graze the pasture too short and attempt to eradicate the weeds without making other changes, the only thing you're doing is making the chemical companies richer.

Call me what you will, but I certainly don't want to get onto the chemical merry-go-round.