In my garden plot it is spotty but there is a large pile of composted manure next to it that presumably came out of the barn. Peas grown in that compost show very severe deformities. Likewise with the manure still in the barn. Too bad all that wonderful fertilizer is useless. In the vegetable garden there are hot spots and places where things grow jus fine.

As I bioassay soil samples out in the east pasture I find slight contamination in a few spots and growth of peas just fine from most. The closer to the barn and feeding trough the more curling of the leaves I see.

I know picloram is even more persistent in the soil and compost than clopyralid. I have several questions.

If I see damage in my bioassay but it is just slight curling of the leaves, would it be safe to till the land and plant grapes next year?

What do I do with the large amount of contaminated manure? Is there a way to speed up degradation of it? I guess this degrades the slowest in compost.

In my vegetable garden with pretty high concentration of hot spots from the manure, realistically how long will it take before I could grow sensitive plants like tomatoes and beans?

Are there any new developments on bioremediation of these pyridine carboxylate herbicides?

Thanks.

http://www.puyallup.wsu.edu/soilmgmt/clopyralid.htm

This site also has good info
http://www.the-compost-gardener.com/picloram.html#axzz1zaBBTkjK

I have read all of the WSU information. Very good information and that is what I am using for my bioassays on a small number of samples. I really need to get a tractor so I can properly till the pasture.

I was hoping there would be newer information on bioremediation. We desperately need to develop some bugs that will break this stuff down as I see it becoming a larger and larger problem for gardeners all over.

I can't dump my manure out in the south pasture because it is next to a waterway and the picloram would leach into it. I think I may just leave it where fit is and keep tilling it for a few years.

I always worry when I see people advertising horse manure (composted or otherwise) for sale. Most people will not think to ask about herbicide application to feed and/or straw. They get this stuff, run into problems and then blame "compost" for their problems.

Lloyd

I second the advice of growing what will grow. Plant a cover crop, till it in. Plant another cover crop, till it in. I would also till in some good compost if you can get it. The beds that have we have made sure to water extensively. I have also placed worms from my worm bins in the hopes of breaking it down further. We considered activated charcoal but the quantities needed were beyond our budget.

If you can, I would probably just move the vegetable garden to a better/less sensitive location. Depending on the cost of grapes, you could try just 1 and see how it does but I would not invest a lot of money until you have a better idea of how they will be affected.

for instance, i have a feed trough mounted on a trailer to feedblivestock. this moves around the pastured areas. where the trailer sits for a while, no weeds grow for up to two years. contaminated feed?

since i raise my own feed, i know that is not so.

i also have a hard time buying mostly anecdotal evidence from anyone over the mountain if data used in registering a label. if you do not know what it takes to register, look into it. it's easier to buy a handgun in chicago.

as far as remediation procedures, nope, no luck. the quick results are removal and replacement. charcoal seems difficult to use in field situations. intersting research using willows poplars in leaching noxious stuff, but it seems to be mostly used in waste water/grey water targeting heavy metals.

best bet seems to be a couple quick turn cover crops.

or given the fact that you have a bit of land, don't use the areas you know to be a problem for a while...cuz regardless of how you view the problem, everyone agrees it goes away in time. it's just a question of how quickly.

I am curious though, whether tests are required that would detect this persistent effect on non-target plants? I worked in this field for awhile but I was doing soil and aquatic degradation studies on the chemistry side, to determine degradation half-life and degradation products. I didn't do bioassay type of work at all so I'm not familiar with that side. It seems like that is what this would require. Does the FIFRA registration package include that?

Unfortunately my east pasture is the optimal place for grape vines. The other spots have potential for flooding and/or not suitable sun exposure. Fortunately my limited bioassay so far shows that much of the pasture may be ok with some "hot" spots. I will till the entire 3/4 acre field and plant a legume cover crop to get a better idea of how much is out there. Then I'll till it again in the fall. Hopefully I can still plant most of it next spring with grapes.

2,4-D damage:

Dupont who rec

To treat an acre, it would take about 290 pounds of AC. The cost for 290 pounds (40lbs per bag) on the multavita site is around $590 plus shipping. That seems cheap to me compared to the alternatives.

Anyway, I think it is moot as I have determined that the highest concentration of contamination is in the areas where the hay was dumped and piled up. There is a large pile of composted hay and manure that is probably 30x30 feet and 10-12 inches or more deep. I can see the pattern in my garden on the edge of this pile where the herbicide has leached in as the plants get increasingly more damaged the closer they are to the pile. It looks like contamination out in the field is more spotty and much less concentrated. I'm hoping a good tilling regimen to expose the soil to the sun and another year will be enough to reduce the amount to nontoxic levels. I plan to till my acre and put in a cover crop of beans or peas to do a full bioassay of the field.

Speaking of which...unless I am mistaken...and I have not read a label for these herbicides in some time...does not the label say certain crops are not to be grown until a bioassay test comes back clean?

You're doing the cover crop rotation...in north dakota...that means three years?

The problem with labels is that the information is valid for proper use and location of the herbicides. But they are ending up in places they were never meant to be.

I will plow my vineyard in a few weeks and plant some peas to do a more complete bioassay.

It is easy for most of you to say this chemical or that chemical is bad. Most of you manage your backyards. For those of us that manage quite a bit more than that for agricultural purposes life is not so simple!

Perhaps the problem here isn't so much that evil chemical company, but your local public works dept or DOT that is using the wrong tool to get a job done. This problem has been around long enough for them to know better. Instead of moaning about Dow or DuPont why don't you pick up your phone and research if someone is making bad decisions managing your local public lands?

Find out what your own community/county/state's policy are about using this type of herbicide on public lands at the beginning of what is so often a blind chain of distribution. Just consider that the problem here might not be the chemical as much as it is some government entity's poor agricultural management.

Pyridine carboxylic acids do what they do it really isn't an unknown anymore. As someone who actually manages grazing land and livestock, I assure you I spend a great deal of effort choosing the right chemical and the right strategy for a job. If I'm going to use something like picloram I know I have a responsibilty to manage that use until the chemical is innate. If I don't want that responsibilty (or expense) then I don't use that product. Why should you expect any different from the county or whatever other government agency is managing the land?

It doesn't mean they don't spray and it doesn't mean the ditch isn't hayed. It means different strategies are used that are appropriate for maintaining the hay and it's harvesting, keeping in mind it's final destination.

In the fall of 2011, I spread the manure over the 15' x 20' area of lawn/quack grass. Spring 2012, I pulled the quack grass which was easy as roots had entered the loose manure. This exposed the underlying soil and incorporated some of it with the manure. I build a sheet mulch bed around the perimeter. Next I drenched the contaminated soil with active aerated compost tea made with high nutrient compost and well spiked with activated effective microorganisms (EM - brand used ProBio Balance Plus, manufactured by SCD). I did this twice, deeply raking the surface to oxygenate the soil micro-organisms without destroying them. Then I planted the manure area with corn and the sheet mulch area with various squashes, both of which produce much biomass and are the least susceptible to pyralids. I also did a weed survey, finding less than 10 misshapen and malformed weeds of three species along the margins. Three weeks after planting, I did another soil drench with AACT and EM. I also ensured adequate watering (mostly rainfall with a bit of irrigation

By mid July the corn was waist high and the squash were rampant enough that drivers heading up the street would brake suddenly for a better look. I harvested 40 ears of mid-quality corn and more than 120 pounds of high-quality squashes. The best was the weed survey completed at the end of August. Fourteen different species in robust health. The biomass will stand over winter, collecting snow and moisture, then in the spring, I'll chop it and add it back to the soil and do another AACT and EM soil drench.

I'm wondering if perhaps AACT and EM along with biomass accumulators and ensuring soil moisture might help remediate your contaminated soil?