Farmers advised to delay spreading manure
Farmers are encouraged to wait to spread manure until after the snow has melted and the ice in the ground has thawed.
The Minnesota Pollution Control Agency said manure that is spread while the ground is thawing and the snow is melting has a higher chance of running off fields and entering ditches, streams and other water sources that combine with ground water.
That runoff can introduce harmful bacteria or nutrients to the water sources and contaminate groundwater, Glen Roberson said. He is the district manager for the Goodhue Soil and Water Conservation District.
To avoid this, he said that farmers should try to monitor how much manure they are spreading and to follow the Minnesota regulation of staying at least 300 feet away from surface waters and open tile intakes when applying manure.
Robertson said farmers should test nutrient levels in manure samples so they know exactly how many nutrients are being applied to the soil. He said in many cases, too much manure -- and therefore too many nutrients -- are being applied.
Regulating exactly how much manure is being applied to the soil is also key. Robertson said farmers should calibrate their manure spreaders to properly distribute manure amounts.
"Know how much you're putting on," he said.
Robertson said the SWCD can connect farmers to the resources they will need to do manure nutrient tests and to help farmers calibrate manure spreading machines.
Even though manure run off can be a pollutant to the water, "don't waste it because it's a valuable resource," Roberson said.
If farmers do waste it, it can also have environmental impacts. There are "always consequences," he said.
If manure spreading cannot wait, the Minnesota Pollution Control Agency says to follow these guidelines:
1. Apply on fields with less than a 6 percent slope for solid manure or 2 percent slope for liquid manure.
2. If possible, stay farther away than the required 300 feet of surface waters.
3. Keep as far back as possible from areas of potential water flow.
4. Spread on fields with the most crop residue; 30 percent residue is recommended.
5. Avoid fields that have areas full of remaining ice and snow.
6. When applying, keep application amounts minimal to avoid runoff.
7. Try to avoid applying it to land that connects to land that will remain untilled, like ditches, streams and ravines.