By Glen Arnold, CCA, Ohio State University Extension
An unusually dry fall has allowed manure application to farm fields to be ahead of the normal schedule. Nevertheless, there will still be some application of manure to frozen ground or snow-covered ground.
Permitted farms are not allowed to apply manure in the winter unless it is an extreme emergency, and then movement to other suitable storage is usually the selected alternative. Several commercial manure applicators have established manure storage ponds in recent years to help address this issue.
In the Grand Lake St Marys watershed, the winter manure application ban from Dec. 15 to March 1 is still in effect. Thus, no manure application would normally be allowed in that time period.
In the Western Lake Erie Basin (WLEB) watershed, the application of manure to frozen and snow-covered soils require there to be a growing crop in the field. This could be a pasture, alfalfa, clover, ryegrass or a rape crop. There must be enough vegetation visible to provide 90% cover of residue and growing vegetation. Radishes and oats would not qualify as a growing crop as both are typically winter killed. Manure can be applied to fields without growing crops if the manure is incorporated at the time of application or incorporated within 24 hours of application. There have been many acres of cover crops planted this fall, but the extremely dry weather has prevented robust emergence.
The rainfall rule for surface manure application in the WLEB is a weather forecast saying “not greater than a 50% chance of a half inch or more of rain in the next 24 hours.” It is advisable to print out the weather forecast when you start applying manure so you have the needed documentation if an unexpected storm drenches the area. Weather.gov is the most commonly accepted website for this forecast.
Although not required by law, winter manure application should follow the NRCS 590 standards, which limit solid manure application amounts to five tons per acre and liquid manure application amounts to 5,000 gallons per acre. These have 200-foot setback distances from ditches, streams and creeks and must be on slopes of less than 6% and less than 20-acre areas in size without additional buffers.
For liquid manure application, examine fields for tile blowouts, monitor tile outlets before, during, and after manure application and any other situations that might allow manure to reach surface waters.