Funder, over at It Seemed Like A Good Idea At The Time, was asking about composting and horse manure the other day. The last couple of weeks have been crazy at school (even before Halloween kicked in), so I promised to get back to her. Last night I left such a long comment that Blogger didn't even want to accept it. (I tried three times, and then when I looked, it had posted three times! Oh well, that's what the trash can is for.)
Then I got to thinking that the whole saga needed illustration, so here is a slightly expanded version, with photos.
Although I've looked into some very high-falutin' technological systems for composting my manure, I actually take a very simple approach.
I bed on pellets, so it is really easy to keep the majority of the bedding out of my compost pile (I would say less than 10%). Pellets are also known to decompose the fastest of any bedding material (except maybe shredded paper, though that has other issues). During the winter I pick my stalls nightly, if the horses have been in (I only give them access in the really bleak weather--wet and cold--except for my old retired boarder, who has 24/7 access to his stall). Each stall has it's own muck bucket and fork, so this goes quickly.
My pile is out from the end of the barn about 40-50 feet. I spread the compost on my 12 acres or so of pastures in the spring, and leave just a small "starter" pile for the coming winter--mostly from the little manure collected over the summer from the grooming stall and horse trailer, and from a fall "stripping" of the stalls. By spring I'd say my pile is probably 30' by 30' and 8-10 feet high (as high as my little tractor bucket can reach).
Each weekend, the muck buckets get emptied into the tractor bucket (I know, I'm WAY spoiled! but after all, I'm dealing with five horses--at one time ten) and dropped on one side of the manure pile. I do a more intense job on the stalls, especially any wet spots (here's where bedding gets in to the pile); again, into the tractor bucket and out to the pile.
I either pick the paddocks, or use the tractor to scrape the really popular spots; all then goes to the main pile. In some of these older photos, where you see quite a bit of hay and/or straw, it would be either foaling stall straw or wasted hay from around the tire-feeders I used to use (my new-last-year slow feeders have really cut down on that!)Once all that "fresh" manure is deposited, I use the tractor bucket to turn the opposite side of the pile towards/over the new material. Just like kneading bread, each week I choose a different spot to add my new material and fold from the opposite side. I lift the bucket high to better mix, shred and aerate the material.
We are on the back side of the mountains, as Funder is, so it is a dryer, high desert climate in summer. I will occasionally let the irrigation sprinklers hit the pile, if I think it is getting too dry. At that point I'm not adding much, if any, new manure, as the horses are on pasture 24/7 and I just drag the pastures with a blanket harrow to work the manure in every so often. In the winter it's not usually sopping wet, so I haven't ever had to tarp my pile--though once or twice it has gotten a bit soggy, it always recovers. I don't add any additional "dry" material (other than the occasional bad hay bale).
At various times this pile (or two, when there were more horses) might have actually been in one of the paddocks. The older horses pretty much left it alone, but sometimes the babies [Jackson!] would decide it was a great place to play and romp! So now that I'm down on numbers I can leave it out of reach in my "extra" paddock.
When I go to turn the pile it is always steaming hot. I suppose I could worry about the "optimal" temperature, but I know that it's definitely hot enough to kill any weed seeds, parasite eggs, or other unwanted contaminants.
It also might be interesting to note that I don't have much of a problem with flies in the summer. I think if I went to the trouble of adding the fly predators to the pile in the summer, I probably wouldn't have any!I still turn the pile from time to time over the spring and summer, after the horses go out on pasture and I've stopped adding new material. It will continue to "cook" most of the way to fall.
It usually takes me two half days to spread the compost on the pastures. I got the New Holland 50 bushel spreader for my 2007-2008 birthday/anniversary/Christmas presents. I got the PTO version (instead of ground-driven) because it gives me more options for unloading--including just piling it up in one spot (this came in handy on another composting project that I will save for a future post). (These three photos are from the first year I had the spreader--it was actually a little late to be putting the compost on the fields, as the ground was starting to freeze. But I had to play with my new toy! Not to mention getting the previous year's piles out of the way for the coming winter.) I'll use a little for a few planters--it's rich and dark and works just as it is for most plants. Evergreens especially like the slightly acidic nature of horse manure, but I think that composting eliminates any danger to other plants. This is also one advantage of having some bedding material or old/moldy hay incorporated in with the manure--it reduces the nitrogen levels a bit, which is where horse manure gets the reputation of "burning" plants--I've never had a problem with this, however. I think I've mentioned that I'm death to plants, so I don't garden in any formal sense--no veggies and only flowers that can take care of themselves. This planter was just old cedar split posts and rocks, filled with compost straight out of the pile. (I did let it age there for one more winter before I finally got around to adding seeds.)