It holds moisture and adds organic nutrients that help soil long after application
In Wisconsin, Clark Riemer describes his grain operation as “farming in the Arctic Circle.” He claims many farmers from other states would rather place his land in the Conservation Reserve Program than attempt to farm it. Despite the challenges, his 1,000-acre corn, soybean and wheat farm provides for both his and his brother’s families.
Riemer says his soils are low in organic matter and water-holding capacity and need nitrogen, phosphorus and potassium. When he went looking for a cost-effective, profit- and yield-increasing solution for all three issues, he found it in pen-packed manure from a nearby cattle operation.
“We saw a dramatic yield increase the first year and continue to see yield impact up to three years after (manure application),” Riemer says. “We save money on nutrients, but the biggest benefit I see is the organic matter it adds. It’s like putting a sponge down to hold water.”
The manure delays moisture and drought stress eight to 10 days compared to fields without manure in his sandy loam soils, he adds.
While he has experienced many benefits of using manure, he takes certain precautions. “A couple of different areas to consider are risk of compaction and runoff,” says Kevin Erb, a Certified Crop Advisor, agronomist and conservation training coordinator at University of Wisconsin Extension.
Applying manure into fields can create soil compaction, reduce root growth and lower water infiltration. Tillage can break up compaction, but it’s best not to compact the soil in the first place, Erb says.
“What are the high runoff areas in the fall, or especially in the winter?” asks Laura Good, soil scientist at the University of Wisconsin. “Understand what the leeching potential of soils are. Avoid application at times and in areas where it’s likely to get washed away.” Also check with your state for specific guidelines concerning manure application near surface water or other sensitive areas.
“Most states require tests to see nutrient content,” Erb says. “Nutrients will vary based on animal type, the feeding system, rain, etc.” When you learn what your manure has, adopt application to crop needs.
“One of the biggest concerns is the social aspect,” says Natalie Rector with the Michigan Corn Growers Association. “The odor issue is the biggest deterrent. The best way to avoid it is to incorporate.” Most importantly, use common sense. If your neighbor is having an outdoor wedding or party, don’t spread manure in the field next to them. Communicate with neighbors on timing.
Watch for E. coli and other pathogens. “You need to be aware of where you are potentially spreading so you don’t spread in a way that infects groundwater,” Erb says. Manure needs to stay where it is applied to reduce risk.
“Some believe they picked up 20 bu. per acre because of manure in dry years,” Erb adds. “Over time, building the soil’s organic matter can increase holding capacity by an additional 0.5" to 1" of water.”