This tidy horse farm has learned how to manage its manure. Instead of building a mountain, compost bins have been conveniently set up to convert waste into organic fertilizer. Photo by Alayne Blickle.

If you care for horses on your own property, then at some point you have probably wondered what to do with that huge mound of horse manure piling up behind the barn.  Add to that the 8 to 10 gallons of urine a horse generates, plus the wheelbarrow or more of bedding used each day, and in no time at all, you will have a virtual horse manure mountain.

There are many concerns for the mismanaged horse manure pile—besides wasted space. Horses allowed to graze near their own manure are quickly re-infected with the larvae that hatch from worm eggs shed in manure. Odor and fly problems can be a concern to you or your neighbors. Plus, run-off from soggy manure piles can cause serious water quality issues for creeks and wetlands, as well as for drinking water. Many areas of the country have ordinances in place that strictly control many of these issues.

Learn how to control that horse manure with your very own composting system that easy to implement and simple to maintain.

Composting Simplified
All organic matter eventually decomposes, including manure and bedding. By providing an ideal environment for beneficial bacteria and microorganisms, we can speed up the process, thereby  reducing the volume of waste and turning it into a valuable end product—compost.

As manure and stall waste break down, the microorganisms generate tremendous amounts of heat. This heat can destroy weed seeds, fly larvae, worm eggs, and other disease-causing pathogens. Finished compost is a crumbly, earthy-smelling, dark material which happens to be a marvelous soil amendment for gardens, landscapes and pastures.

Composting is an excellent manure management technique that backyard and small-acreage horse owners will find easy and wonderfully beneficial. Among the benefits, it:

• Reduces fly populations by killing larvae and eliminating breeding grounds.

• Reduces odors (a properly managed compost pile should smell earthy and pleasant).

• Reduces worm eggs, parasites, weed seeds and other disease-causing pathogens.

• Reduces the total volume of material—composting decreases the size of the manure pile by about 50% in 2 to 4 months.

• Provides a free source of valuable soil amendment for pastures, gardens and yards. Your horseless neighbors may find it a valuable commodity as well!

Reap Rewards from Waste Recycling

• Position your compost pile close to your horse’s home, away from neighboring property, and away from watersheds. • Set up two or three compost piles to keep the removal and ready-to-use cycle in balance. • Turn and aerate your piles to speed decomposition and reduce odors. • Use the “squeeze test” to make sure your compost pile has the right amount of moisture. • Use finished compost to treat your pastures from late spring through early fall.

• Saves money—over the course of a year, the manure one horse produces is worth somewhere around $200 to $350 (maybe more!) in compost.

• Reduces the chance of manure-contam-inated run-off from reaching surface or ground waters.

• Makes property healthier and more pleasing to look at and enjoy.

Finished compost is a precious soil amendment, one infused with micro- and macronutrients that work in a timed-release fashion. Compost adds life to soils in the form of beneficial bacteria and fungi. Academic research has shown that compost makes plants healthier and more disease-resistant. Just a single application can have benefits lasting five or more years. Compost will also help soil hold moisture, which is very important in helping pastures survive summer drought.

Bins or Piles?
In order to compost and generate heat, it’s important to stack your manure and stall waste at least 3 to 4 feet high. The bin design provided with this article is a good size for generating heat as well as for chore efficiency, and can be managed without a tractor or fancy equipment.

Larger horse facilities, and folks with tractors, might need a sturdier bin design with stronger walls, a roof, and a cement pad. For these situations, look for design help and technical assistance from one of the resources listed in the sidebar “Build Your Own Compost Bin” on page 29. Individual consultants may also be able to help you assess your manure management options based on the size of your operation, equipment and other resources.

But you don’t need to have a bin to compost. The bin merely provides some organization and aesthetics to the situation. Composting can also be done simply with piles.

Managing the Compost System
Managing the composting system includes tarping, turning or aerating, and watering. Like most living things, the microorganisms that break down the manure and bedding are aerobic, requiring air and water. Too much—or too little—of each can cause problems. Here are some simple steps to facilitate the process:

1. Choose the right location. Begin by locating an appropriate site for your compost pile. Choose an area convenient for chores. (Easy access to your barns and paddocks will increase the chance that you’ll clean more frequently.) You’ll want your manure pile in a high, well-drained area that’s far away from waterways. Locating it at the bottom of a hill, or in a wet area, is a bad idea. When it rains or snows, the site will turn into a pile of mush and make it hard to access. A dry, level area is especially important when it comes to accessing the pile with any kind of heavy equipment, such as a tractor or truck (which you may want for the finished compost).

2. Piling. Deposit daily manure and stall waste in one bin or pile. When that bin or pile is a large as you want it (and at least 3-4 feet high), leave it and begin building a second pile or bin, and so on. In two to four months, the first bin or pile should be completely composted and ready to use. It’s a good idea to have at least two or three separate piles.

Composting Space Requirements

When planning out your composting system, here are a few things to consider: • For a backyard composting system with one to five horses (without the use of a tractor or heavy equipment) use two to three 8' x 8' x 4' bins or piles. • If you are going to use a tractor to turn your compost, plan on two to three 8' x 8' x 4' piles (or bins) for one to five horses. When using a tractor, it helps to place piles (or bins) on a cement pad. This makes it easier for the bucket to scrape the surface and keeps the tractor tires from tearing up the ground. • A 30' x 30' area will house three piles with some room to move. • For larger composting systems (five horses or more) where heavy equipment will be used, you may want to consider two three-sided cement bins approximately 16' x 16' or 35' x 35'.

3. Keep it covered! Covering your compost will prevent valuable nutrients from getting washed away, as well as  keep run-off from causing problems with the neighbors or ending up in nearby waterways. A cover will prevent piles from becoming a soggy mess in the winter and too dry in the summer. You can cover your compost with tarps or plastic sheets, or by building a roof over the tops of the bins.

Tip: If you live in a windy area, weigh down your tarp with boards or milk jugs full of gravel. Since you will need to pull the tarp back every time you clean your horse’s stall and paddock, make the tarp as chore-efficient and easy-to-use as possible. You may want to attach your tarp to the back of your compost bin with nails or a staple gun.

4. Get air into the pile. Turning the compost-to-be allows oxygen to get to the bacteria and other organisms that break down the material into dirt-like structures. This keeps the process aerobic and earthy smelling. If the compost becomes anaerobic—without air—it will have a foul, undesirable odor.

How often you turn the pile will help determine how quickly your compost will be ready. On its own, air will permeate the pile to a depth of 1 to 2 feet, so it’s the center of the pile that really needs air. However, turning the pile can be difficult unless you have access to a tractor, or enjoy a good workout.

An easy way to get air to the center of the compost pile, while avoiding the necessity of frequent turning, is to insert a couple of 5- or 6-foot PVC pipes into the center of it, like chimneys. Buy PVC pipes with holes in them, or use a drill to put holes along the pipes. The pile will still need to be turned occasionally to get the manure on the outside into the center, so heat from the composting process can kill parasites and weeds more evenly.

5. Keep it damp. Your compost material should be about as damp as a wrung-out sponge. Particularly in the summer, you will need to find a way to water your compost pile—either with a garden hose when you turn it, or just to hose down the manure in your wheelbarrow before you dump it in the pile. The compost should be damp but not dripping with water. If you squeeze some of it in your hand (you can wear a glove if you want!), you should only be able to squeeze out a drop or two of moisture.

6. Monitor the temperature (optional). A wonderful component of composting is the heat generated by the beneficial microbes. A compost pile can get fairly warm—about 130° to 150° F. If you want the compost to kill fly larvae, worm eggs, weed seeds and pathogens, you need it to reach these temperatures for about three or four days. You can monitor the temperatures easily with the aid of a long-stemmed compost thermometer, available at local nurseries or home and garden stores.

7. Finished compost. How actively you monitor the air and water, and how often you turn the pile determines how quickly the manure and bedding will compost. It should take around three months to finish, perhaps longer in the winter. You will know your compost is ready when the material looks evenly textured, crumbles like dirt, and is no longer like the original material. The heat, too, should have dissipated from the pile. It should be 90° F or less in temperature.

8. Put that black gold to good work! Compost is a rich soil enhancer that improves the health of both plants and soil and helps to retain moisture. You can use your compost in your garden, give it away to your neighbors, or spread it on your pastures during the growing season—late spring to early fall. You can use a manure spreader, or simply spread it with a shovel from the back of a pickup truck. To avoid smothering grass, don’t  spread it too thick. A sprinkling of a quarter- to a half-inch at a time (and no more than 3-4 inches per season in the same area), is about right.

So now you know that when manure happens, you have a wonderful plan to make compost happen! How’s that for hitting pay-dirt?