Spreading manure too early may lead to runoff problems later

Courtesy of deere.com
During harvest season, farmers are short on time and may rush to clean out their manure pits early and get them out of the way, but this can mean trouble if it’s a rainy fall harvest season.

"Right now, the September-through-November forecast from the National Weather Service gives us equal chances of getting above- or below-normal rainfall, so it could be a rainy fall," Sara Walling, water-quality section leader with the Wisconsin Department of Agriculture, Trade and Consumer Protection, said. "One good downpour or a string of rainy days could carry manure straight to streams if you're not careful,"

Fortunately, most farmers have tools that assist them in making choices on the best time to spread manure. One of these tools is the Wisconsin Manure Management System’s Runoff Risk Advisory Forecast. This tool gives farmers maps with updates that happen three times daily. The updates take into account the weather forecast, slope, soil moisture  and crop cover. This allows farmers to determine the risk of spreading manure into their own watershed basin.

"We know farmers want to get their manure pits emptied before winter sets in and makes spreading more difficult, but right now, there's still time, and we encourage them to use caution – and to use the advisory forecast, " Walling said. "Whenever you have to spread manure, follow your nutrient-management plan because it includes all site-specific risk areas on your farm. If you don't have a plan, talk to your crop consultant or county conservationist to develop one. They may also help you find alternatives to spreading in risky conditions. You might be able to stack manure away from lakes and streams, drinking-water wells and sinkholes or exposed bedrock. If you can't avoid spreading, they can help you identify fields where the risk is lowest. If you don't know how to find your county conservationist, go to DATCP's online Conservation Directory."