Sammy, did you know that goats will eat just about anything, even the nettles? I would definitely recommend that you let them graze the area before you plant. Goats are now being used in many communities to graze on invasive weeds including kudzu.
One of my favorite weed killers is vinegar. Yup, you can use the 5% vinegar from your pantry if the weeds are small and young. If you have something as resistant and difficult as burdock or thistle, you may need horticultural vinegar. It's about 15% to 20% acidic. It's non-selective and will kill whatever it splashes on. From this site from Mother Earth News under 'Vinegar vs. Weeds ...'.
When killing broadleaf weeds, regular white vinegar, at 5 percent acidity, works well. Be careful when handling and spraying not to get any of the vinegar in your eyes. Some people experience skin irritation with vinegar too.
The best time to spray is on a windless day, early in the morning Ã¢â‚¬â€ make sure that a hot, sunny day is forecast. I like to use my pressure sprayer with plain vinegar. To spray, cover the leaves of the weed thoroughly and spray the crown of the plant. In about an hour, the leaves should be drooping. By the end of the day the weed leaves will be all shriveled up.
Vinegar doesn't necessarily kill the root of the weed, so reapplication may be necessary. The younger the weed, the easier it will be to kill. For me, vinegar has knocked out Canada thistle, dandelion, plantain and burdock.
Sometimes [url=https://www.vet.purdue.edu/depts/addl/toxic/plant02.htm]people confuse burdock[/url] with [url=https://www.vet.purdue.edu/depts/addl/toxic/plant32.htm]cocklebur[/url].
This is an interesting Canadian site. I selected a weed. Once you get the recommended list you can click on the Herbicide Reference Links on the right. If you select 'Grazing Restrctions' it explains alot.
Here's a report from Dodge in Lethbridge, AB in July 2006. He used cooking vinegar at 5% acidity.
ok guys so far this is what I've figured out, but first a bit of info about my horses. First my horses have never had vinegar in their diet so they might not be attracted to it for that reason, if you do feed your horse vinegar make sure they arent attracted to whatever you sprayed it on.
Basically I tested burdock plants in several ways
First I just sprayed the leaves and left it for about two days. Within the first 5 hours the leaves I had sprayed were dead and shriveled. Unfortunately the rest of the plant was fine. So that was sorta a no go. Besides the bigger an area you spray the more grass and other growing organisms your going to hit. So for me less exposure and spreading was a big key in my experiment.
So second experiment, I cut the burdock (this one I tried stood about 1 foot and 1/2 tall and had about an inch thick stem base, it was also starting to flower) leaving about 3-4 inches of stem off the ground. (If all I did was cut the burdock like this or to ground level it would grow back and bigger than before) So then I soaked the stem in regular house-hold vinegar, and for fun I dug a mini moat around it and soaked that too. Note this was all done with a spray bottle, not dumping from the container of vinegar. I left if for three days, checking it at least everyday to see the progress. This is what I've come up with so far. In the three days the vinegar has killed about 2 inches of the plant completely and it has also killed another inch of the core, but still leaving some growing on the outside layer (im not talking about leaves, but burdock is sorta like celery, and the "strings" on the out side of the burdock were still living.)
For me thats pretty good results.
I also tried another burdock plant except I cut it down all the way to the ground and sprayed it with the vinegar, of course all I can see is the dead top but I'm more than ok with that.
Well thats what I've got so far if anybody has any questions don't be afraid to ask.