Considerations When Developing Farm Maps

Farm maps communicate important farm management information and can be important for supporting manure and nutrient applications when developed as part of nutrient balance sheets. Key map information includes: field name, field size, fields receiving manure applications, the location of setbacks or buffers from surface water or environmentally sensitive areas, and the location of farm features such as manure stacking areas. In developing farm maps several items should be considered.

1. Identifying farm field locations: On maps, field boundaries should be drawn as managed by the farmer. The field name or identification should be clear. If a field boundary is incorrect, it can impact the mapped field acreage and the soil information reported for the field.
2. Identifying setbacks and buffers: If setbacks overlap a mapped farm field, the total field acreage may not be suitable to receive manure. Suitable acreage equals the total field acreage minus the setback acreage. The suitable acreage calculation may become important when determining the total amount of manure that can be applied to a field. The PAOneStop mapping application can be used to calculate suitable acreage.
3. Dividing fields: Dividing fields on a farm map should reflect a farm management decision made to meet farm management goals. When dividing fields to account for farm management changes or for long-term setbacks, the field identifiers must be clear and consistent with other farm information and documentation such as nutrient balance sheets. Over the long-term, dividing fields can lead to changes in soil fertility.