As the poultry industry continues to grow throughout the lower Southeast — especially in Alabama and Georgia — the total amount of nutrients or litter available for land application increases. But in north Alabama, a recently enacted rule bans the spreading of animal manure on the state's pastures and cropland from Nov. 15 to Feb. 15.
While many animal waste vendors are not pleased with the new rule, some experts say the ban is an essential step toward safeguarding Alabama's surface and groundwater.
The poultry litter ban, announced more than two years ago by the Alabama Department of Environmental Management (ADEM) and based on best management practices developed by the Natural Resources Conservation Service (NRCS), was implemented this past May.
Some of the region's certified animal waste vendors, who make a living from cleaning out poultry houses and spreading the manure as fertilizer on pasture and cropland, believe the ban will force some of them out of business. While conceding that the ban places a hardship on many vendors, an Auburn University expert says it is necessary to reduce the rising levels of nutrients from animal manure that are leaching into the groundwater or washing into surface water.
“Many growers find it convenient to clean out their poultry houses during this time of year,” says Extension agronomist Charles Mitchell. “Unfortunately, from the standpoint of water quality, this really is the worst time of year if the litter then is applied to pastures or cropland.”
From November to February, most cool-season crops, such as fescue, ryegrass and small grains grow very slowly or not at all in north Alabama in spite of the ample rainfall that usually occurs during this time of year, says Mitchell.
“You get high levels of precipitation and very low levels of evaporation, and what happens? The nutrients from this manure leach into the groundwater or wash off into the Tennessee, Warrior or Coosa rivers.
“As a result, growers end up losing money because the crops are bypassed by the nutrients and left unfertilized,” says the agronomist. “Equally bad or worse, growers may be contributing to surface and groundwater contamination.”
Under best management guidelines established by the Natural Resources Conservation Service, animal waste vendors are advised to apply nutrients only to actively growing crops or within 30 days of planting.
Some of the highlights of Alabama's new nutrient management standards include the following:
Soil test every field where nutrients are applied at least every three years.
Periodic manure testing (table values may be used in planning).
Nitrogen rates should not exceed 10 percent of the state Land Grant recommendations for the intended crop.
Phosphorus rates should not exceed 10 percent of state Land Grant recommendations for the intended crop except where animal manures and other organic byproducts are used.
Phosphorus Index will be used to make a risk assessment of each field where animal manures and other organic byproducts will be applied.
Manures and organic by-products are not to be applied within three days of a predicted storm event with a probability of rain of less than 49 percent.
Nitrogen should be applied only to actively growing crops or when they are within 30 days of planting. Therefore, no animal manures or organic by-products are to be applied between Nov. 15 and Feb. 15 in north Alabama because rarely are crops actively growing during this period.
Farmers who want to get the most from their fertilizer should apply it at the time of year when the crop needs it the most, says Mitchell.
“Usually, most of the phosphorus and potassium and some of the nitrogen is applied at or near planting or early in the growing season with the remainder of the nitrogen applied later. Cotton and corn are not fertilized in the fall, and bermudagrass is not fertilized in December,” he says.
The following recommendations from the Auburn University Soil Testing Laboratory specify the optimum time of nutrient applications:
Bermuda/bahia pasture: On summer grass pastures, apply phosphorus and potassium as recommended and 60 pounds of nitrogen before growth starts. Repeat the nitrogen application up to Sept. 1, when more growth is desired.
Fescue pasture: Apply Nitrogen, phosphorus and potassium as recommended by Sept. 1. Repeat nitrogen application in February.
Small grains and ryegrass for grazing: For small grains and ryegrass planted on fallow fields in early September for grazing, apply 100 pounds of nitrogen at planting and 60 pounds in early spring. Ryegrass planted alone for grazing should receive no more than 60 pounds of nitrogen in the fall and up to 100 pounds in early spring. For grains only, apply 20 pounds of nitrogen in the fall and 60 to 80 pounds in the spring. The fall nitrogen can be eliminated following a good soybean crop or other legume.
The bottom line, says Mitchell, is that the application of nutrients — particularly nitrogen and phosphorus — during the late fall and early winter in north Alabama is not a sound practice, from an agronomic or environmental standpoint.
“Only under unusually mild weather conditions and in certain locations would nutrient application be advisable during this same time period in central Alabama. In most years, some growth of cool-season forages can be expected in south Alabama from November through January.”
The north Alabama poultry litter ban poses a special challenge to poultry breeder operations, which produce eggs for broilers and operate 365 days a year. Unlike broiler producers, who typically can wait a few months before cleaning out, breeder producers have to clean up after every production cycle.
Breeder litter also tends to be much wetter than broiler litter — a factor that makes disposal even more difficult during the winter.
Fortunately, for breeder operators and vendors, experts are working on several solutions for temporarily storing the waste until it can be applied in the spring and summer.
Alternatives include shallow trenches enclosed by dikes where the litter can be stored without being leached or washed out during heavy rainfall. Other options include special sheds and bins where the litter can be stored or composted until spring.
The Tennessee Valley Resource Conservation and Development (RC&D) District, comprising eight north Alabama counties, also has developed several collecting sites and composing and dry-stacking facilities for waste vendors who aren't able to comply with the guidelines.
“We're telling producers that if it comes down to the wire and you've got a consignment of litter that you can't apply, you can contact the Tennessee Valley RC&D to find alternative uses,” says Mitchell. “Litter can be used as animal feed or hauled to south Alabama.
Technically, only vendors in the eight counties comprising the district — Limestone, Madison, Jackson, DeKalb, Marshall, Morgan, Lawrence and Cullman — are eligible for these benefits. However, it's likely the district will be willing to work with other vendors pending the availability of funds.
For more information, contact the RC&D poultry litter hotline at 1-866-548-8123.