In-crop manure application increases crop yield
August 14, 2012 – A nutrient management specialist with Manitoba Agriculture, Food and Rural Initiatives reports in-crop applications of liquid swine manure fertilizer can result in up to a 10 per cent yield increase over the standard fall application.
In-crop manure application was among the topics discussed recently as part of a field clinic in soil and manure management at the University of Manitoba’s National Centre for Livestock and the Environment. Clay Sawka, a nutrient management specialist with MAFRI, says most manure fertilizers in Manitoba are typically applied in the fall but, by applying in-crop, farmers can spread out their workload and hopefully provide nutrients when the crop needs it most.
“Generally we see liquid manure being applied to the grass crops that can stand a little bit more damage,” says Sawka. “Just like your lawn when it gets cut, the growing point is below the ground so we can go in there and apply manure to those crops in about the two to five leaf stage, so early in the year when we still have lots of time to bounce back from any impact of the traction or the implement itself.
“We’ve had reports of up to a 10 percent increase in yields over the standard fall application of 100 percent of your nutrients,” he says.
“These guys are generally putting down starter N with their seed and the topping up with the remaining 100 to 120 pounds of nitrogen and seeing about a 10 percent bump in yields.”
Conditions are very important.
“You have to have the right conditions so that manure is not still lingering around in the surface,” says Sawka. “If the soil is too wet, you see a little bit more compaction issues, some more disturbance from the rolling tines going through so you want to try to time it with the crop conditions, that two to five leaf stage, as well as trying to not hit the soil when it’s too wet. Drier soil conditions are much better.”
Sawka acknowledges there will be years when in-crop application works and years when it doesn’t so it’s a gamble to try to apply all of your manure in that narrow two to five leaf window.
He says when it works it works well but there might be years where you just can’t get on there because the soil conditions just aren’t right.