As manure becomes more of an asset to no-tillers than a waste product, the state of Pennsylvania is looking into new ways to deal with the old problem of keeping manure in fields rather than water sources.
This year, Pennsylvania is using a $225,000 federal grant to study the benefits of injecting manure into farm fields. The purpose is twofold: To see if no-tillers receive better fertilization from having manure injected, and to reduce on-the-farm odors.
No-tillers in Berks, Lancaster, Fulton, Dauphin and Bradford counties are participating in the program. For three years, haulers will inject the manure on select fields, where soil scientists and crop experts will monitor soil health and fertility.
While the injection process is more expensive than traditional spreading, scientists believe no-tillers could save on reduced fertilizer costs, says Jeff Graybill, an educator with Penn State Cooperative Extension in Lancaster County.
At the same time, injecting manure reduces runoff and nearly eliminates the problems associated with odor, Graybill adds. That is crucial as Pennsylvania faces federal mandates to reduce the amount of farm runoff entering the Chesapeake Bay watershed.
“We need to reduce the amount of nitrogen and phosphorus that is getting into the bay,” he says. “This is one way that we are looking to meet that goal.”
Scientists are targeting dairy farmers for the pilot program because they have a ready supply of liquid manure that is easily injected into the soil.
Participating haulers are using a system that slices a small slit into the soil, injects the manure about 4 inches deep and then pushes sod back over the hole, Graybill says.
“The things we looked at is how did it affect growth, and did it make things difficult to plant,” he says. “Their planters did a good job in that respect.”
No-tillers can lose over half of the nitrogen to the air when it is spread on the surface, Graybill says. However, through injection, farmers are saving 80% of the nitrogen. That means a farmer could use about 5,000 gallons of manure by injection, rather than 7,000 gallons for over-the-top fertilization.
“We can put on less manure per acre and get the same fertilizer advantage,” he says. “We are using it more efficiently.”
One drawback to injection, however, is that haulers have to charge no-tillers more because the process takes longer, Graybill says. Hopefully, any increased cost for the hauling will be offset by savings in fertilizer costs.
“The farmer needs to see the benefit,” he says.
In every case, farmers that are participating in the program practice no-till.
“We are trying to marry the benefits of no-till with the environmental benefits of injecting manure so you don’t have the odor issues or environmental problems with runoff,” Graybill says.
No-till is starting to catch on in Bradford County, because the practice helps farmers work more efficiently on an already-shortened growing season, says Mark Madden, an extension educator in Bradford County.
However, broadcasting manure onto established cover crops is not the most effective way to deliver fertilizer to plants, he says. This fall, after farmers have taken off their corn for forage, manure injectors will visit as many as 20 farms for the experimental program.
Brian Garman, a Lancaster County dairy farmer who milks about 50 cows, says he has seen no difference in his crops since the injection.
However, during the initial application, Garman says he noticed high nitrogen levels in the soil. That concerned him because that might kill off earthworms, which are important for overall soil health.
Still, Garman is interested to see the overall results of the study because he likes incorporating manure into his fields to help with crop growth.
“It is a good source of fertility,” he says. “I prefer that over commercial fertilizer because it has more organic matter in it.”