Organic Mulches May Boost Transition from Plowed Land to No-Till

February 12, 2002

WOOSTER, Ohio - Farmers looking to convert their plowed land to no-till may be able to control disease pressure and improve soil fertility by spreading organic mulches such as animal manures and composts.

Ohio State University researchers have found that adding organic mulches helped to decrease the time it took to convert from plow-till to no-till, with the benefits of the mulches showing up within the first year of application.

"It usually take a few years, two to five, to successfully convert plow-till to no-till, especially with clay soils, because there are more insect and disease problems," said Warren Dick, a soil science researcher with the Ohio Agricultural Research and Development Center (OARDC). "We found that the organic amendments helped to stimulate the microbes in the soil to counteract disease organisms and reduce their expression in the field."

Dick said that adding manures to fields to improve soil fertility is common, but using high rates of manures (or composts) to aid in the transition of plow-till to no-till is a relatively new idea. Dick will discuss how the impact of various mulches can jump start no-till practices at the Conservation Tillage and Technology Conference, Feb. 25-26 in Ada, Ohio.

Over 50 speakers from land-grant universities, the farming sector and agricultural industries and organizations will be speaking at the two-day conference. The program will cover a wide range of topics including agriculture-related panel discussions, strip till research, weed and pest management, soil fertility, GMO crops, value-added farming, crop consulting, soil and water quality issues, precision agriculture and producer programs.

No-till farming is a practice whereby the residue from the previous season's crop remains in the field and the new crop is seeded directly into the residue. No-till farming is a popular conservation farming technique because it helps control soil erosion, conserves and improves water quality, and stores more carbon in the soil than plowed land. Hence it improves soil quality and helps reduce carbon inputs to the atmosphere that are thought to be the cause of global warming.

But there are some management issues associated with no-till farming, including problems with increased insect and disease pressures. Though insects and diseases can be controlled with crop rotation, adding organic mulches with a proper carbon-nitrogen ratio at the onset of field conversion provides an initial biological and nutritional boost to help keep insects and diseases in check.

"The organic mulches provide a slow release of nutrients, like nitrogen, phosphorus and potassium that tends to match the requirements of the crops throughout the growing season," said Dick. "In our studies, we found that we didn't have the yield depressions that you normally see when planting into clay soils that had been tilled but now are being converted to no-till."

He recommends a one-time high rate mulch application of about 15-to 20 dry tons per acre and then an annual three-to five dry ton per acre application for as long as the farmer is able to apply the organic amendments. "Depending on the location of the farm, organic mulches, like animal manures and yard trimmings, are easy to come by and are cheap," said Dick. "If farmers do use organic mulches, we recommend they add the mulch in the fall to give the decomposition process time to get started."

Sixty-percent of corn and 24 percent of soybeans in Ohio are grown on no-till land. In 2000, crops were grown on over 50 million acres of no-till land throughout the country. Part of the Ohio State study was conducted at OARDC, where researchers have been managing no-till for 40 years, the longest continuously maintained no-till test plots in the world.

The tillage conference is being sponsored by Ohio State University Extension, Northwest Ohio Soil and Water Conservation Districts, United States Department of Agriculture Natural Resources Conservation Service, USDA Farm Service Agency and the Ohio No-Till Council.

Early registration is $20 per day or $30 to attend both days. Registration after Feb. 11 is $30 a day or $40 for both days. For a copy of the agenda, registration information, or directions to Ohio Northern University, contact the Hancock County Ohio State Extension office at (419) 422-3851 or the Allen County Soil and Water Conservation District at (419) 223-0040.

Author(s): 
Candace Pollock
Source(s): 
Warren Dick