Fall manure application is a crucial part of the farming cycle, bridging the gap between crop harvest and the onset of winter. While crops may have been harvested, there is still essential field work to be done to ensure economic and agronomic benefits for farms while minimizing environmental risks and adhering to application policies.
In the context of this article, fall manure application typically occurs between crop harvest and winter or after September 1st for perennial crops. It's essential to follow the state's definition of winter related to manure application, which includes specific conditions such as the period between December 15th and February 28th, snow-covered ground, or frozen soil at least 4 inches deep. Winter manure application is discouraged due to its associated challenges, including increased setbacks from surface water features and potential environmental risks.
Fall manure applications take place when traditional cropping systems are dormant. However, the widespread use of cover crops in the region offers a safety net for nutrient retention. Cover crops play a crucial role in incorporating nitrogen and phosphorus into their plant tissues, effectively storing nutrients until spring when they are needed for crop growth. These cover crops act as a biological reservoir, exemplifying why they are often referred to as "green manure." Additionally, cover crops provide erosion protection, preventing nutrient runoff and soil loss.
Proper planning is essential when considering manure application to ensure that farms do not exceed their storage capacity in the upcoming months. Applying sufficient manure now can prevent the need for winter applications, which are less favorable due to various economic, agronomic, and environmental factors.
In Pennsylvania, all manure applications must adhere to the guidelines of a manure or nutrient management plan. To determine the appropriate plan, farmers can contact the county conservation district and request assistance from a conservation specialist. Planning offers the advantage of determining a balanced manure application rate based on anticipated crop yields for the following year.
This rate considers the crop type and expected yield, estimating the necessary nitrogen and phosphorus for the next year's crops. By setting this nutrient demand ceiling, farmers can avoid overapplication of manure nutrients, ensuring maximum yield while minimizing the risk of nutrient runoff.
Calculating the final manure rate involves subtracting nutrients that are already expected to be available to the crop. This includes nitrogen from previous manure applications or legume crops, phosphorus in the soil, and nutrients from fertilizers or other organic sources. The rate determination also considers the percentage of manure nitrogen available to the next year's crop.
For precision in manure application rates, soil testing and manure analysis are recommended. While these tests may incur costs, they generally result in improved nutrient utilization efficiencies, making them a wise investment for farmers.
Another critical aspect of manure application planning is the establishment of setbacks. These setbacks, which determine the distance between manure application sites and surface water features like streams, lakes, or ponds, are vital for preventing water contamination. Properly planned, documented, and followed setbacks serve as an essential defense mechanism against water pollution and ensure compliance with manure application regulations.
Several professionals, including plan writers, certified manure brokers, and conservation specialists, can assist with manure application planning. Approaching fall manure application with a comprehensive understanding of nutrient management and risk mitigation, coupled with the goal of retaining applied nutrients for optimal agronomic and economic returns in the coming year, is essential for the sustainable practice of farming.
Categories: Pennsylvania, Crops