Whether you are riding on a trail or your horse is in your stable, it produces manure, lots of manure. Not only for appearance sake, but also for health and safety, it is important to clean up after your horse. Thankfully, horse manure is relatively dry which makes picking it up easier than other animal manure.
In the Pasture
If you house your horse in a small pasture or paddock you need to pick up the manure and remove it from the field. This is because fresh manure left where the horse grazes contains parasites that the horse may ingest. Move the manure either to the edge of the pasture, spreading it out so it will eventually line the pasture, or to your compost pile where it will break down slowly. In larger pastures, or if you rotate your horses' grazing from one field to another, the manure can be left alone. If you can, though, go out and spread the piles of manure out so that it can dry out faster, thus killing the parasites quicker. Because of the high nitrogen content in horse manure, spreading the piles out in larger pastures will benefit the pasture grasses. You might even practice your golf swing by using a golf club to spread the manure around.
In the Stable
Horse manure in and around a stable area can be more of a problem. Many horse owners and stables will create a large pile of manure and bedding that is offered to gardeners or farmers. Because of the warmth fresh horse manure has, most growers cannot use it until it decomposes. If you can find a grower that would like your manure heap, it will probably be after it has decomposed for a month or more, unless the grower is about to till his land and wants to spread and work the manure into the soil. In many areas the local government has a compost drop-off at their waste facility. Call to check if they accept horse manure and what quantity. You will probably need to transport the manure yourself. Finally, grow your own garden and establish a compost heap of your own. Composting will reduce the manure by as much as 75 percent. Make sure you locate the heap away from streams or other water sources and neighbors.
On the Trail
What trail you choose to ride on will determine if you need to remove your horse's manure. Some trails have a requirement that a rider stop and clean up after their horse. Check before venturing out so you can bring the necessary equipment. Some trails only require you to move it into an adjoining field while another may want you to carry it out and dispose of it on a compost pile at the end of the trail. It always better to check first so you are prepared.
If you rotate your horses from field to field, you may want to invest in a small manure spreader that you fill with manure and spread with your tractor on the field not being used for grazing. By using a spreader and watering, the manure will break down quickly and enter the soil. The grass will benefit greatly from the added fertilizer. If you just want to get someone to come and get the manure, look for a mushroom farm in your area. The manure and bedding mix from your stable is a perfect growing medium for mushrooms. And the mushroom farm will need the supply all year long, unlike a farmer.