Environmental equine: Mucking out may merit make-over

Few horse owners know what nutrient management entails. Rumors swirling throughout the Bay states have many concerned that Big Brother will make it impossible to keep horses. The truth is that nutrient management will affect owners in heavily populated areas near sensitive waterways. But compliance shouldn't be inordinately expensive or difficult, and it shouldn't prevent anyone from keeping horses. Even if your state doesn't yet require that you have a nutrient management plan, your pastures, your streams and your neighbors would all benefit from your doing so.

The goal of nutrient management legislation is to reduce the amount of P and N leaving the land on which they are applied. To achieve this, the regulations limit how much of these nutrients can be applied to fields. The details of each state's laws vary greatly; some limit nitrogen and phosphorus, some only nitrogen. Some include horses, some don't.

Maryland's law - which at press time is the most complicated and inclusive - requires anyone with eight animal units (one animal unit equals 1,000 pounds of live-animal weight) to have a nutrient management plan. Because horses are designated as two animal units, anyone with four or more horses must comply. Plans must be updated every three years. Several key details of Maryland's legislation are still being worked out.

Delaware's law dictates that anyone with eight animal units have a waste management plan, which provides specific guidelines about where and how to store manure and document what is done with it. In Delaware, one horse equals 1.25 animal units, so only properties with seven or more horses must comply. Also, if you apply fertilizer to 10 or more acres, you must have a nutrient management plan. (Virginias and Pennsylvania's legislation excludes horses; the federal law covers "animal feeding operations" so large as to exclude most stables.)

Farmers have been using nutrient management plans for years. Getting a plan is fairly straightforward: Soil tests determine the levels of various nutrients, and a nutrient management adviser can analyze how these levels meet the needs of a target crop. If nutrient levels are higher than what's needed, the landowner is advised against adding fertilizer until nutrient levels have dropped. Local Cooperative Extension offices can help, as can Southern States' GrowMaster professionals.

Of the Maryland stables that have developed nutrient management plans since the law was passed, the problem hasn't been the presence of too much nitrogen and phosphorus, but too little. Typically, horse pastures aren't fertilized and limed enough, even taking into account the manure left by grazing animals.

What to do with stall waste presents more of a problem. Gone are the days of dumping manure in the woods for Mother Nature's disposal. Now you will have to account for how it is stored and what happens to it once it leaves storage.

Waste management is complicated by the increasing urbanization of rural areas: Where once your barn was isolated, suddenly neighbors are peering over your fences, wrinkling their noses. The last thing you want to do is invite complaints by having a messy, smelly manure pile.

The local Soil and Water Conservation District can advise you on the best location for a manure pile. If you have enough horses and stall waste to warrant building a manure storage structure, the SWCD can design it for you at no charge and help you determine if you qualify for cost-share dollars to offset construction costs. Creative ideas for manure management will be addressed in the next issue.

Nutrient notes Get a nutrient management plan, and follow its recommendations. If your pastures need lime and fertilizer, don't be afraid to apply them; the healthier your pastures, the less runoff that will occur. Not only does grass absorb nutrients from the soil, it also acts as a physical barrier to prevent runoff. Take care of bare spots. Take horses off grass that has been grazed below three inches, and don't let them back on that grass until it is six inches high again. Keep horses off wet pastures as much as possible. In winter, always keep hay in the pastures to discourage horses from grazing grass that is dormant and can't rejuvenate. Clip pastures regularly during the growing season to keep weeds under control. Mowing also promotes more even grazing by cutting back older, less palatable grass. Drag pastures to break up and spread manure. This not only makes more of the nutrients available to grass, it also helps kill parasites. Pile manure and stall waste as far from water sources and neighboring houses as possible. Cover manure piles with a tarp during wet weather. Compost manure and spread it on gardens or croplands or have it hauled away. If you spread manure on your property, do so only during the growing season. Don't spread when the ground is frozen and can't absorb the nutrients.