– Glen Arnold, CCA, OSU Extension Field Specialist, Manure Nutrient Management and Kevin Elder, Livestock Environmental Permitting, Ohio Department of Agriculture
With warmer than normal weather forecast for the next couple of weeks, corn and soybean harvest in Ohio is expected to get back on track. Livestock producers and commercial manure applicators soon will be applying both liquid and solid manure as fields become available.
For poultry manure, handlers are reminded to stockpile poultry litter close to the fields actually receiving the manure. Stockpiles need to be 500 feet from a residence, 300 feet from a water source and 1,500 feet from a public water intake. Poultry litter cannot be stockpiled in a floodplain and cannot have offsite water running across the litter stockpile area. The site also cannot have a slope greater than six percent.
Litter stockpiles need to be monitored for insect activity and steps taken to keep insect populations in check if necessary. Farmers receiving poultry litter from a permitted facility need to have their fertilizer certification training completed. While field application rates of two to three tons per acre of poultry litter are common, farmers should still have soil tests and manure tests taken so manure nutrients being applied are fully utilized by the following crop rotations.
For liquid manure applicators, examine fields for tile blowouts, soil cracks, worm holes, and any other situations that might allow manure to reach surface waters. Old clay tile that are not charted, and may have an outlet buried in the bottom of a ditch, have caused a number of manure escapes in Ohio over the years. Recent manure escapes into ditches in northwest part of the state have caused fish kills and resulted in fines being levied. Farmers and applicators need to monitor field tiles for several days after application to be sure manure does not escape with the next rainfall event.
Liquid manure application rates are limited to the moisture holding capacity of the soil or no more than a half inch or ~13,500 gallons per acre for tiled fields. Limiting application rates below legal limits can help keep more nutrients on fields. Remember, a corn-soybean rotation will remove about 120 pounds of P2O5 over two good growing seasons. That will drop your soil test phosphorus level about 6 pounds per acre. Applying high amounts of manure can rapidly raise soil test levels and result in greater losses of phosphorus from farm fields.
Incorporated liquid manure or liquid manure incorporated within 24 hours does not have a setback requirement from ditches and streams this time of year. If just surface applied, with no plan of immediate incorruption, a vegetative setback of 35 feet is recommended or a 100 foot setback if there is little or no vegetation growing in the field. These recommendations for non-permitted farms and are the rules for permitted farms.
The Western Lake Erie Basin watershed rule for surface manure application is a weather forecast saying “not greater than a 50% chance of a half inch or more of rain in the next 24 hours. For very heavy soils (typically Hydrologic group D) ¼ inch of rainfall can cause runoff when combined with a half inch of liquid applied on the surface. It’s advisable to print out the weather forecast when you start applying manure so you have the needed proof if an unexpected storm drenches the area.
The rain forecast does not apply to incorporated manure. However, the soil must be fractured and disturbed when manure is applied to qualify for incorporated. Just poking holes in the soil does not qualify as incorporation. Deep incorporation of manure nutrients could help break up the phosphorus stratification issues that may be contributing to the increasing levels of dissolved phosphorus leaving Ohio farm fields.
For permitted farms, when more than 50 pounds per acre of manure nitrogen is being applied, it’s required that a field have a growing crop or cover crop be planted. In manure amounts, this could be a little as 1,500 gallons per acre of swine finishing manure, one ton of poultry litter, 3,000 gallons of dairy manure, 1,000 gallons of liquid beef manure, or five tons per acre of solid pen pack manure.
All farmers should consider utilizing cover crops with manure applications to capture the available nitrogen and turn it into organic nitrogen in the form of additional roots and stems. Livestock producers in the Western Lake Erie Basin watersheds must have a growing cover crop in the field if they intend to apply manure to snow covered or frozen soil this winter. The cover crop should cover at least 90 percent of the soil surface.
Cover crops can help livestock farmers recapture manure nutrients and conserve soil by reducing erosion. The goal is to combine nutrient recovery and protecting the environment. With weather forecasters predicting above average temperatures the remainder of October, there is still time to establish good stands of cover crops.