Japanese Knotweed - Anything kill this stuff? Any weed experts here?

J

JasonM

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JM
Posting this is a long shot, but I have been fighting with these nasty Japanese Knotweeds on my property ever since I bought the place over 12 years ago. I can't find anything that will kill this crap permanently.

Is there anything stronger than glyphosate concentrate?

I have injected gasoline, diesel fuel, and every weed killer I could find into these things, tried mowing them, burning them and more; yet every year they sprout right back up.

I would think killing something like this would not be so hard to do.
 
Is it in a field or near water? One of the courses I had to take to get my applicator license dealt with this stuff.

Don't till it, that'll make it worse. Hand cut or mow every week or two spring through fall. Pull out as much as you can, getting as many of the roots as possible. (don't compost that stuff, either).

Control may take a couple years, depending on how much of it there is. Roundup isn't going to work on its own. Try finding an herbicide with Triclopyr, Imazapyr or Picloram in it. You need something that'll kill shrubs/woody plants. I don't think you'll need a license to buy this stuff. May not find it at Home Depot, but if there is a place that the local farmers/orchardists buy their stuff, go there. You may also find that adding a bit of horticultural oil (we call it 'summer oil') will help the chemical adhere to the plant.

Be very, very very careful with the chemicals if the plant is near water. It gets in the water it'll kill stuff downstream, including any little animals and bugs that live in the water. Not good.

This stuff isn't going to die in a year. It will take two or three years. And even after that, you have to monitor the area, as the rhizomes are pretty tenacious. Keep mowing, keep pulling and follow the mixture directions on the bottles of chemicals. More isn't going to kill it faster.

I have a PDF that I saved from when I was studying. I'll see if I can find it. The above stuff is from notes that I took.
 
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Thanks. It is crazy stuff! Amazing how resilient it is. It is mostly near a small stream which is likely why it grows like crazy. I have tried pulling it, but the roots are so big it is almost impossible. I took a dozer to an area once and that only made it spread throughout the area. I just cant believe there is not something out there that would kill this crap. Best I could find is some bug in japan that will eat it, but that doesn't help me.
 
EdFred said:
How about some goats?
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Goats will eat all your weed problem.

Tenacious plants the only thing you can do is kill the root system through starvation. So you either pull them out of the ground cleanly, or you cut off every shoot it sprouts so it loses photosynthesis capability, but this may take a long time to be effective.
 
Personally I think the easiest way to deal with this stuff on a residential or commercial property is through managing the growth into a garden feature. It's much easier to manage the growth in a pleasing form than it is to kill it. It's also better karma.
 
Amitrol T used to work, but it was canceled by the EPA and was always restricted-use. I used to have an applicator certification and was able to buy it, but I let that expire years ago. It killed pretty much everything.

Maybe some other triazole herbicide would work, but I'm not sure any of them are available any more. If they are they're probably restricted-use.

Rich
 
Does the area get a lot of sunlight? If so, get a large sheet of clear plastic. Say its 16'x16'. Dig a small trench about 15'x15'. Cover the area with the plastic, bury the edges of the plastic in the trench. Let it sit for a while.
 
EdFred said:
How about some goats?
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Henning said:
Goats will eat all your weed problem.
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I'm gonna go buy some damn Goats! :yes:


Henning said:
Personally I think the easiest way to deal with this stuff on a residential or commercial property is through managing the growth into a garden feature. It's much easier to manage the growth in a pleasing form than it is to kill it. It's also better karma.
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I don't want this stuff, I don't want to look at it anymore. Some idiot before I owned the place thought it was a good idea to plant it in the yard. :mad2:


RJM62 said:
Amitrol T used to work
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You know where one can find some of this said Amitrol? I'll pay the damn EPA fine if it kills this crap. :D
 
UngaWunga said:
Does the area get a lot of sunlight? If so, get a large sheet of clear plastic. Say its 16'x16'. Dig a small trench about 15'x15'. Cover the area with the plastic, bury the edges of the plastic in the trench. Let it sit for a while.
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I'd say not really a lot of sunlight. there is a lot of trees around shading the area. I should try that though.. Thanks.
 
JasonM said:
I'm gonna go buy some damn Goats! :yes:




I don't want this stuff, I don't want to look at it anymore. Some idiot before I owned the place thought it was a good idea to plant it in the yard. :mad2:




You know where one can find some of this said Amitrol? I'll pay the damn EPA fine if it kills this crap. :D
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I'm not sure that Amitrol or any of that genre are still produced for our market, you'd probably have to get it from India and smuggle it like heroin. If you buy a goat, get a bred Nubian nanny so you get milk too. Goats make good pets, but they take a fair amount of care, especially hoof care.

Other wise you can do what the goat does and keep cutting it back till it dies.
 
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As soon as I read the title, I cringed. I HATED that stuff in Colorado. Never did get it eradicated. I hope you do!

Goats are great for the surface stuff, but you'll need some pigs for the roots.
 
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Henning said:
I'm not sure that Amitrol or any of that genre are still produced for our market, you'd probably have to get it from India and smuggle it with the heroin. If you buy a goat, get a bred Nubian nanny so you get milk too. Goats make good pets, but they take a fair amount of care, especially hoof care.
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We already have horses, so dealing with some goats should not be a big deal. The horses don't like the knotweed at all though.
 
Archammer said:
As soon as I read the title, I cringed. I HATED that stuff in Colorado. Never did get it eradicated. I hope you do!

Goats are great for the surface stuff, but you'll need some pigs for the roots.
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Can goats and pigs live together? :dunno:
 
salt the ground. will kill everything - but then you need to replace the soil. . .
 
JasonM said:
We already have horses, so dealing with some goats should not be a big deal. The horses don't like the knotweed at all though.
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Oh, if you have horses, goats are a perfect fit, way better around your property than severe toxins. They are completely symbiotic in a pasture because they eat different things, goats don't like grass, goats want weeds, and they will keep your pastures weed free as well. Goat milk is great for the first three days, then it, and any goat milk product, tastes like a Billygoat smells. I'd walk out in the morning with my coffee with sugar in it, call up Betsy and put a few squirts of milk in my coffee.

You can often rent goat herds for brush clearing projects.

The thing about goats though is you have to put up the goat wire (like hog wire but with 12"x6" squares so they can turn their heads and get back through, otherwise you are constantly going out and getting them unwrapped.) if you need positive retention. Barbed wire does not hold them at all.
 
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comanchepilot said:
salt the ground. will kill everything - but then you need to replace the soil. . .
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Really? Seems strange to me as we use a lot of salt in the winter on the porch and it all goes into the ground around that with flowers etc that have never had any problems growing. Is there a special kind of salt?
 
JasonM said:
Definitely need a goat now. :yikes:
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Read my edit on fencing, I don't know your situation or how important being able to keep then secured on your property is. There is only Goat Wire to use, nothing else works, I don't care how close and tight you string it or how hot you electrify it, you will find them on the other side of it.

It's not a big problem as far as them running away, they won't, but if you have to keep them in, there's only one way, and you may as well prep for it, because you're going to have a herd of goats for a long time controlling that stuff.
 
JasonM said:
Really? Seems strange to me as we use a lot of salt in the winter on the porch and it all goes into the ground around that with flowers etc that have never had any problems growing. Is there a special kind of salt?
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It's a matter of concentration, but if you're going to do it it means digging out all the soil behind it and cleaning or replacing it if you ever want something to grow there again in your lifetime. It's the "Nuclear Option" of ancient warfare.
 
Henning said:
Read my edit on fencing, I don't know your situation or how important being able to keep then secured on your property is. There is only Goat Wire to use, nothing else works, I don't care how close and tight you string it or how hot you electrify it, you will find them on the other side of it.

It's not a big problem as far as them running away, they won't, but if you have to keep them in, there's only one way, and you may as well prep for it, because you're going to have a herd of goats for a long time controlling that stuff.
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This is our setup now for bettyLue. As you can see the rope keeps her at bay, but if she breaks out, we have the moat. :)

original_koe_4sm.jpg


In all seriousness, I will likely use some of this stuff, since we already use it on some other fenced in areas.

OurFamilyOfFence.jpg


Henning said:
It's a matter of concentration, but if you're going to do it it means digging out all the soil behind it and cleaning or replacing it if you ever want something to grow there again in your lifetime. It's the "Nuclear Option" of ancient warfare.
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I'm fine with that also. I can haul in new dirt.
 
JasonM said:
This is our setup now for bettyLue. As you can see the rope keeps her at bay, but if she breaks out, we have the moat. :)

original_koe_4sm.jpg


In all seriousness, I will likely use some of this stuff, since we already use it on some other fenced in areas.

OurFamilyOfFence.jpg




I'm fine with that also. I can haul in new dirt.
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Goats are the much better solution looking at your situation. The roll wire stuff you want is the one that has the 12"x6" openings.
 
JasonM said:
Really? Seems strange to me as we use a lot of salt in the winter on the porch and it all goes into the ground around that with flowers etc that have never had any problems growing. Is there a special kind of salt?
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I'd follow Henning's advice first - goats like weeds.

The amount of salt is intense.
 
TEFLONSEAN said:
This stuff is excellent and long lasting.

Think you mentioned problem was near a stream. If it is....this product may be a no go.

http://www.mrochem.com/Barren_p_10.html

Banned in a lot of states...but not yours!!!!
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Very risky product, though. One of the actives is something called Bromacil, which is a systemic, root-absorbed herbicide that can migrate laterally and kill adjacent plants.

Rich
 
RJM62 said:
Very risky product, though. One of the actives is something called Bromacil, which is a systemic, root-absorbed herbicide that can migrate laterally and kill adjacent plants.

Rich
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Sounds like some good stuff. :yes:
 
JasonM said:
Sounds like some good stuff. :yes:
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You have to be very careful with it. Don't apply it when the soil is moist or rain is predicted, for example. It can stay active in the soil for a long time and may drift or leach to contact the root system of non-target plants.

Personally, I'd lean toward one of the other, non-chemical solutions if possible. But I'd make book that a root-absorbed herbicide like bromacil would be as good a bet as any to control this particular plant if you decide to do it chemically.

The other active ingredient is 2,4-D, which is both leaf- and root-absorbed and hyper-stimulates plant growth. The combination of the root-absorbed bromacil (which interferes with photosynthesis, although I don't remember how) and the 2,4-D is a one-two punch that I doubt many plants could survive.

See if you can find a label for the product. It may (or may not) list the specific plants it's effective against.

Rich
 
RJM62 said:
You have to be very careful with it. Don't apply it when the soil is moist or rain is predicted, for example. It can stay active in the soil for a long time and may drift or leach to contact the root system of non-target plants.

Personally, I'd lean toward one of the other, non-chemical solutions if possible. But I'd make book that a root-absorbed herbicide like bromacil would be as good a bet as any to control this particular plant if you decide to do it chemically.

The other active ingredient is 2,4-D, which is both leaf- and root-absorbed and hyper-stimulates plant growth. The combination of the root-absorbed bromacil (which interferes with photosynthesis, although I don't remember how) and the 2,4-D is a one-two punch that I doubt many plants could survive.

See if you can find a label for the product. It may (or may not) list the specific plants it's effective against.

Rich
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I'm going to buy some and try it on a small area.
 
gee, thanks. Reading about this noxious weed made me go back to googling how to get rid of bindweed - one of Colorado's most prolific weed, it seems. Now I'm really discouraged. Almost enough to wish for another foot or two of snow over my dormant bindweed back yard.
 
JasonM said:
We already have horses, so dealing with some goats should not be a big deal. The horses don't like the knotweed at all though.
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Horses and goats do well together. There was a time when it was fairly common to keep a goat with a racehorse as a companion animal.

However, do make sure your fences are up to spec, they're escape artists, and they like to climb on things. Normally they climb on rocks and hills, but vehicles and buildings will do in a pinch.

the-world_s-top-10-best-images-of-climbing-goats-5.jpg


the-world_s-top-10-best-images-of-climbing-goats-8.jpg


You also may want find out what kinds of sounds they make as well.

 
FormerHangie said:
Horses and goats do well together. There was a time when it was fairly common to keep a goat with a racehorse as a companion animal.

However, do make sure your fences are up to spec, they're escape artists, and they like to climb on things. Normally they climb on rocks and hills, but vehicles and buildings will do in a pinch.

the-world_s-top-10-best-images-of-climbing-goats-5.jpg


the-world_s-top-10-best-images-of-climbing-goats-8.jpg


You also may want find out what kinds of sounds they make as well.

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:yikes: I may need to think about this goat thing...
 
JasonM said:
:yikes: I may need to think about this goat thing...
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We had between 100 and 300 depending on where in the breeding/market cycle we were. There is no more enjoyable livestock, especially at kidding time. The kids are so much fun.
 
Henning said:
We had between 100 and 300 depending on where in the breeding/market cycle we were. There is no more enjoyable livestock, especially at kidding time. The kids are so much fun.
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I told the wife and she wants a herd of them now.. :mad2:
 
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