2,4 D in a Huge Pile of Horse Poop

So my neighbor raises horses, his horses eat hay that has been treated by 2.4 D, his horses poop in a huge pile that would be otherwise useful if it wasn't for the potential presence of the herbicide.

One of the piles is at least 2 years old, and I was considering using it to fertilize my growies... have I lost my mind?

My personal experience with horse manure was pretty dismal. The neighbour's horses are pumped full of chemicals and their hay with herb and pesticides, so of course when I put the manure on ALL of my garden, things stopped growing. It took about 4 years to get it growing to normal again.

However, your neighbours' manure might be a lot better. Maybe try a little bit on some of the garden (maybe less than 1/4) and see if it has any effect. If it is positive then you know the manure is safe to use, and if it isn't safe, then you won't loose the entire harvest like I did.

I would suspect that since this is only a moderately persistent herbicide, and since it's been 2 years, it's probably ok... but I think it's important to consider the breakdown of the substance.

2,4 D Half life is most likely 180 days in soil... which is about a third of something like Aminopyralid, but that just means it's broken down into other metabolites. Well, what are the metabolites?

2-chlorohydroquinone is the first thing that it breaks down into... well that's also hazardous, but in truth probably at 1000's of times the level that would be in the soil... and even that, of course, has it's own half life.

It's not so much about 'will the garden grow', as it is about 'can I knowingly bring myself to stuff these turds into my hugelkultur.

Personally I would never put suspect materials directly into my food garden. I would compost the material, making sure to boost the fungi populations as much as possible (lots of threads about how to do this, I bet). Then I might use the material as mulch on something other than my vegetable garden, such as support trees or mulch plants. I would want that suspect material to pass through as many biological filters as possible before it got to my food.

Another thing to consider: Are they worming their horses? What are they using?
Some of the commercial worming medicines are persistent for several years.
Say good bye to your worms and other soil life if these wormers are still active.

Since you know the people, I'd test it where it is. I've seeded clover and buckwheat straight onto a manure pile. You could see how well some things like that grow, maybe try a bean, too -- pintos or something cheap like that. You could also dig around and see what kinds of bugs are present. If it's been sitting there for two years, there should be grubs and worms in there.

As previous poster mentioned, do a test. Plant a bean in 2 pots with the aged manure, and in 2 pots with potting soil. If they both grow with no noticeable difference I would use it.

Thanks for all of the replies guys!

Would you really want to introduce 2,4-D to the source of your food supply?

Physiologia Plantarum
Volume 44, Issue 4, pages 395–399, December 1978

The effects of an auxin herbicide, 2,4-D, at a concentration of 0.01 mM, on the K+ uptake and efflux of excised roots of wheat (Triticum aestivum L. cv. Rannaya) were investigated at different pH values. The K+ movement was monitored with a K+ (86Rb) tracer. In parallel experiments the ATPase activities of microsomal fractions were determined by the inorganic phosphate liberation method. 2,4-D inhibited the K+ uptake especially at low pH, irrespective of whether Ca2+ was present or not. No marked changes were observed in the K+ efflux properties at pH values above 4. The inhibitory effect on K+ uptake exhibited a correlation with the hydrocarbon solubility of the herbicide, but not with the 2,4-D-induced decrease of the ATPase activity. It is suggested that 2,4-D exerts a non-specific effect on the lipid-protein interactions, giving rise to a generalized alteration of the transport barrier properties of the plasma membrane even at as low a concentration as 0.01 mM.

http://onlinelibrary.wiley.com/doi/10.1111/j.1399-3054.1978.tb01644.x/abstract

There are better solutions. Have you thought of growing a cover crop in an undeveloped area and porting it over as mulch when you cut it? That nearly free solution will provide a massive nitrogen kick to your garden. Mulch helps with water retention and soil erosion as well. If you're not in favor of mulching, you could till the cover crop in at the end of a season. Tilling burns through organic matter and I'd avoid it where possible; still, it's better than introducing poisons to your garden. Once you introduce 2,4-D to your garden, you live with it or replant elsewhere. Consider this quite deeply before you apply the manure. How much time have you spent building your garden to this point? Are you organic now? What do you give up for 'free shit?' (hehe... had to). In my case, I choose organic gardening so that I know the produce will be nutritious and clear of contaminants.

Hey Chris,

Thanks for that info and citation.

Out of curiosity, what do you mean by 'porting over'?  I have considered cover crops (white and crimson clover) but I wasn't really sure how to till that back in to a 6 foot tall hugel bed.

I am ALL ABOUT mulch, but I was just planning on using grass from my field.  

I don't have any spectacular plans... but I'm just looking at the color of my soil and shaking my head currently...

I would grow the cover crop on different land and mow it to ground level when biomass peaks (about half of the cover crop is flowering at this point). Collect the above-ground trimmings and dump them on the top and sides of your hügelkultur. You'll lose some nitrogen to the atmosphere, but the boost you gain will still be very significant. A good cover crop should provide about 4 tons of biomass from a tenth acre of land; you won't need much area or seed to supplement your large hügelkultur. You'll want legumes more than grasses; they provide much more nitrogen and nutrition for your project. Grasses are typically found in cheap mixes; you need only enough grass to support your legumes.

I see that you mention your hügelkultur in your second post on this topic; I'd missed that and was focused on your 'growies' as mentioned in the initial post. You cannot till into a hügelkultur, nor do I think you'd want to. You could turn the earth a little with a shovel, should you wish. Content you cover will impart more nutrients to the soil. I think you'd get more results from a larger cover crop area than turning the biomass in though, so it's likely not worth the work.

If you want to consider a cover crop to generate biomass for your hügelkultur, this one is a fine choice: http://www.groworganic.com/soil-builder-mix-raw-lb.html

My anecdata, for what it's worth -
My horses eat hay from local farmers that, quite frankly, I do not know the origins of. They probably use 2-4-D among other things, as far as I know no preservatives, but I'd be shocked if these dudes didn't spray. They are also dewormed using commercial/chemical antiparasitic drugs (ivermectin/praziquantel, ivermectin/moxidectin, etc etc). I use commercial soft wood shavings as bedding. I compost the waste from the stalls and the round bale waste from the fields scraped up at the end of the year.  The two finished piles haven't had too much green matter added to them simply by virtue of not having a running lawnmower most of the time. Despite that laundry list of sins, the compost is killer. Everything I plant in it takes off like gangbusters and it's chock-full of worms. So, don't be scared but compost it further with more stuff in it is the best advice I can offer, and I've had no issues with manure from horses that eat hay that was sprayed at some point.

I have found that 2-4-D breaks down very fast in my hot humid environment. I also recently found this report from Clemson on ivermectin. I too have found active large worms in the poo.