The Do’s and Don’ts of Importing Manure
By : Charles White, Assistant Professor of Soil Fertility and Nutrient Management, and Robert Meinen, Senior Extension Associate
Many livestock farms in the region produce an abundance of nutrient rich manure, so much so that they must look for additional land beyond their own farm to spread it in order to prevent nutrient over-applications. By importing manure from these farms, you can both obtain a relatively economical source of nutrients as well as help maintain nutrient balances on cropland across the region. Below are a few things worth considering when you import manure onto your farm.
Do have a plan. In Pennsylvania, any farm that produces or handles manure must have a Manure Management Plan (MMP) unless the farm is additionally regulated by Act 38 or the federal CAFO program, in which case more detailed types of plans are required. An MMP can be written by a farmer and does not need to be submitted for approval but must be made available for inspection upon request by the Department of Environmental Protection or delegated Conservation Districts. An MMP is a simple document that identifies the appropriate rates of manure to be used on different crops in different fields, identifies environmentally sensitive areas such as streams, ponds, wells, or other water sources and provides a place for record keeping. More information about MMPs is available at the Pennsylvania Nutrient Management Program website.
Don’t spread within setbacks from environmentally sensitive areas. Pennsylvania regulations require mechanical manure application setbacks from certain water features. MMPs have a basic setback of 100 feet from surface waters, sinkholes, and drinking wells, but this setback can be reduced in some cases by implementing certain best management practices. If you receive manure from an exporting Act 38 farm, it will come with a balance sheet that may specify an even greater setback of 150 feet from surface water, so check carefully what the balance sheet requires.
Do consider using a manure broker, commercial hauler, and/or commercial applicator to obtain and apply your imported manure. Manure brokers are licensed to take responsibility of manure from exporting farm operations and can write nutrient balance sheets that determine appropriate manure application rates for different cropping scenarios on your farm. Commercial haulers have the right equipment and training to safely deliver manure to your farm. If available in your area, hiring a commercial applicator to make the manure application could be a wise choice, especially if handling manure is new to you. Commercial applicators will have capable spreading equipment with well-calibrated application rates. Their equipment is likely to have rate controllers that can achieve more uniform applications, or even variable rate applications according to a prescription map. Commercial applicators may also be able to offer manure injection services to reduce odors that may offend neighbors and increase nitrogen (N) availability by reducing volatilization.
Don’t apply manure in the winter or other risky periods if you can avoid it. Farms that import manure should do so with consideration for application timing that minimizes nutrient losses and environmental risk. There is no good reason for a farm to go through the effort to import manure only to spread it at a risky time of year or to store it improperly. If importing manure to apply in the fall for use by a crop the next summer, plant a cover crop to scavenge nutrients over the winter and recycle them for the summer crop. If solid manure is to be stored through the winter for more than 120 days, it must be covered or placed on an improved stacking pad. If stacked in-field, keep the stack out of concentrated water flow paths, 100 feet away from surface waters or well heads, locate it near the tops of slopes, and divert upslope water flow away from the pile.
Do consider getting soil tests for the fields where manure will be spread. Without a soil test, MMPs and Nutrient Balance Sheets developed by brokers must use phosphorus-balanced manure application rates. These rates often do not supply enough nitrogen to the crop, so supplemental nitrogen fertilizer must be used. With a soil test, if the Mehlich 3 phosphorus (P) concentration is below 200 ppm, a nitrogen-balanced manure application rate can be used and appropriate rates of supplemental fertilizer can be determined based on the soil test recommendation.
Don’t put a dollar value on the nutrients contained in manure that you do not need according to a soil test or that will not be available due to nitrogen volatilization. Imported manure may seem like a great value when you tally up the total N, P, and K (potassium) content. However, when considering the value of the manure nutrients on your farm, you should only put a dollar value on the nutrients that would replace what you would have needed to purchase as fertilizer. If your soil tests levels for P and K are already above optimum and the soil test recommendation is zero, then the P and K contained in the manure do not have an immediate value to the farm in replacing fertilizer costs. Similarly, the application management of the manure (time of year, incorporation method, use of a cover crop or not) will determine the quantity of available N that can substitute for fertilizer, and only this quantity should be considered.
Taking into account these basic considerations will help you import manure nutrients in a way that is legal, safe, convenient, and economical.