The Scoop on Poop
If there's one thing you can always count on from your horse, it's a constant supply of fertilizer. "In one end and out the other" certainly applies here! A 1,000 pound horse produces approximately 50 pounds of manure per day. Calculating that further, it's about ten tons per year. Add to this 6-10 gallons of urine which, when soaked up by bedding, can constitute another 50 pounds daily. Talk about mounting problems! And I don't mean getting on your horse.
In addition, wherever there is manure, there are parasite larvae. The life cycle of all horse parasites involves departing from the host by way of the manure and then finding a new host in which to complete it. When a horse eats from manure-contaminated ground, it ingests parasite eggs; thus the best way to break the parasite life cycle is daily removal and proper management of the manure.
Manure, even for the smallest farm, requires proper management to control odor, remove insect breeding areas, and minimize parasite eggs and larvae. Daily removal of manure from the stables and small paddocks is essential, as dung and urine create an ideal breeding ground for bacteria and both internal and external parasites. The ammonia and strong vapors from manure and urine are also very irritating - to the eyes and lungs especially.
Break it up!
Manure in the pasture can be rendered less harmful if you break it up by harrowing or dragging to expose it to the elements. This will encourage rapid drying, eliminating favorable conditions for fly larvae and parasite eggs. Also, the ammonia and salts in the manure will be less likely to kill the grass underneath it if it is spread out.
An adequate drag can be homemade from a piece of chain link fencing with a tire or two attached for weight. Dragging can be done several times a year as needed to break up the clods.
Give it back!
Composting is a method of recycling which returns nutrients to the soil in a ready-to-use form. About 20% of the nutrients a horse eats is passed out in his manure and urine, and if the manure is properly handled, about half of those excreted nutrients can be used to feed the pasture. Horse manure is considered one of the most valuable types of manure because it is quite high in nitrogen, very capable of fermentation, and easy to use because it breaks up easily, especially if it contains bedding.
Composted material is relatively odorless, fine-textured, has a low-moisture content and is a useful fertilizer for the soil with minimal odor or fly breeding potential. Another advantage of composting manure is that it helps kill pathogens, fly larva and undesirable weed seeds that may be in it. The volume and weight of the manure and bedding are decreased as well, making it easier to handle for reuse.
Compost is an excellent source of organic matter, nitrogen and other nutrients for the soil. Some studies show that nitrogen in compost is stabilized and not as easily available to the crop as nitrogen from the raw material. Most types of manure usually have a high nitrogen content and are subject to nitrogen loss during composting. Studies are trying to determine the amount of nutrients in fresh manure versus composted manure, but either way, manure puts something back.
From dung heap to gold mine?
Considerations for composting include having enough land area, the effects of composting odors, the potential economic considerations for the size of the farm, and certain environmental factors. Composting manure can be a favorable option in many situations and can make the generated waste more desirable. It can be used in gardens, potting, for nurseries, or as fertilizer for crops. Manure composting could even be a profitable venture if it is sold to nearby gardeners, farmers, and crop, fruit or vegetable producers.
How to compost
You may already be doing it. The manure pile is really a simple, open compost heap. A neat pile can be effective in breaking down the manure and turning it into humus - that dark, loamy fertilizer and conditioner for the soil. It is moist, full of natural bacteria to help it decompose, and is likely already warm - all the ideal conditions for microorganisms to flourish and do their composting job. Simply turn the pile occasionally to accelerate decomposition.
A pile containing manure and bedding is a better combination of ingredients for healthy compost than either manure or bedding alone. Composting straight manure is possible and may create a higher heat, but it can pack too tightly and can become anaerobic, thus it may actually take longer to completely compost. Manure and bedding will produce great amounts of heat as they break down. This increased heat can help kill off undesirables such as weed seeds, parasite larvae and pathogens, but it can also be detrimental if it gets too high, killing off the beneficial microorganisms. Manure and bedding compost will produce a safer range of temperature for the helpful bugs; it will break down more slowly and be ready in a few months. A pile of only bedding will produce little heat and can take much longer to decompose; it could take years.
Says Bryan Butler, Extension Educator, Commercial Horticulture, of the University of Maryland, "The nitrogen in the manure acts like the fire; the bedding is like the wood. For a sustainable 'fire', it must be kept burning with fuel, or bedding. The bedding also aerates the compost and is the carbon source." Thus, there is more benefit from a combination of manure and bedding.
There are other methods of composting manure, such as windrows and bins. Windrows are usually horizontal "rows", longer than they are tall or wide. Large ones can be hundreds of feet long. Active windrows require turning for aeration; heavy equipment, such as a front end loader or specially adapted turning devices that attach to a tractor, may be used for this, going along each side. Passive windrows have air supplied through perforated pipes embedded within the pile and do not require turning; nor do active aerated windrows, which have air forced in. Bin composting is a system of two or three bins or contained areas beside each other, requiring turning of compost from one bin to the next in a sequence.
Turning the composting material is necessary to maintain the proper temperature (104-149°F), moisture content and oxygen levels. The manure compost can be turned whenever the temperature rises above 145°F to prevent overheating, which could kill the composting organisms. A temperature below 104°F may indicate insufficient oxygen and a need for turning to heat it back up. This temperature range may be sufficient to kill off some undesirables without killing off the good organisms.
What about earthworms? "Earthworms will stay around the periphery of the pile where the temperatures are safe," says Bryan. "They do not travel high up into the pile." When the compost is spread on the field, the earthworms from the ground will enter when it is safe.
"To knock the number of pathogens and parasites down, however, the hotter the better," explains Bryan. "Some composts reach a temperature of 160° or more, though not very often. There are basically three types of bacteria, and they work under different temperature ranges. As far as parasites go, though, horse owners should be deworming regularly as well," Bryan adds.
If the composting material seems dry, add water to activate the composting process. Water content lower than 40 percent may result in overheating. If watering is not possible, the temperature may be regulated somewhat by turning. The composting period may take longer, however, if water content is not maintained at a proper level. Take a handful of the compost and squeeze it. If liquid drips out, it is too moist; if it doesn't clump in your hand, it is too dry. Compost can be covered to help retain moisture.
Good quality pastures with nutritious grasses require soils with sufficient organic matter to provide nutrients and maintain soil condition. It is not the heat of summer that kills off the cool-season perennial grasses, but the lack of soil moisture. Organic matter helps keep soil moist and allows it to breathe. Whatever method you choose, recycle that collected manure to where it can do the most good - put it right back where it originally came from - the grass.