By Andi Anderson
When applying manure to fields with a Soil Test P (STP) above 50 PPM, it is important to manage the application rate to minimize environmental P loss. The publication Assessing Nutrient Loss Risk in Ohio, NRCS, 2020 provides environmental P loss criteria based on the STP in a field.
The guidelines suggest reducing manure application rates with the long-term goal of reducing STP, plus increasing the use of other conservation practices to minimize edge-of-field P losses.
Here are the key takeaways:
- Moderate Risk (STP 50-120 ppm): Limit manure application rate to planned crop rotation P removal. Apply to fields with >30% cover or incorporate, use sensitive area setbacks, no surface application in spring without a growing cover, and implement erosion control.
- Higher Risk (STP 120-200 ppm): Limit manure application rate to 50% of planned crop rotation P removal. Apply to fields with >50% cover or incorporate, use sensitive area setbacks, no surface application in spring without a growing cover, and implement erosion control.
- Very High Risk (STP >200 ppm): No P application. Drawdown P with a more intensive crop rotation that includes forages, if possible.
Manure is a valuable resource, but it is important to manage its application carefully to minimize environmental impact. By following the guidelines in Assessing Nutrient Loss Risk in Ohio, NRCS, 2020, you can help to protect water quality and ensure the long-term sustainability of your farm.
Categories: Ohio, Crops