Nutrient Management
Small, pasture-based dairy farms along the north coast of California face a unique set of management challenges both economically and environmentally. In recent years, stricter water quality standards, rising energy and feed costs, and a shift to organic dairy farming have all converged to increase demand for more intensive management of silage fields and pastures. Throughout the country, there is a clear trend towards developing more sustainable agricultural production systems. The concept of comprehensive nutrient management planning has developed over the last decade to provide dairy operators with clear definitions and technical guidance on ways to optimize the value of manure nutrients, while at the same time reducing potential nutrient losses to the environment in stormwater runoff and leaching to groundwater.
According to the USDA Natural Resources Conservation Service (USDA NRCS), the purposes of a nutrient management plan are:
- To adequately supply nutrients for plant production.
- To properly utilize manure or organic by-products as a plant nutrient source
- To prevent agricultural non-point source pollutants such as pathogens and nutrients from entering surface and ground water resources.
- To maintain or improve soil quality
Nutrient Management Planning is a tool that can help ensure that you are getting optimal forage production from your pastures and silage fields. The goal of nutrient management planning is to apply the right amount of each nutrient required for plant growth at the proper time, based on crop/forage requirements and soil nutrient availability—this is what is meant by agronomic rate. The best on-farm source of nutrients is manure. Determining the amount of manure generated on the dairy, the amount of manure nutrients that will be available to growing crops and forages, and the appropriate application rates for individual farm fields can be a difficult process. Recognizing and accounting for potential nutrient losses to the environment during the handling, storage, and application of manure is an additional challenge.
Nutrient Management Planning Involves:
- Sampling and understanding soil nutrient reserves
- Knowing crop and forage nutrient requirements
- Determining the nutrient content of manure
- Estimating total manure production rat
- Applying nutrients to individual farm fields at agronomic rates
- Best management practices for reducing losses to the environment, including soil loss through erosion.
Basic Components of a nutrient management plan
- An aerial photograph of the dairy, and a soils map of the fields.
- Soils and manure sampling results.
- A list of all nutrient sources and quantity (e.g., dry stack, liquids, compost, etc.)
- Realistic yield expectations for crops and forages.
- Recommended nutrient rates, timing, form, and method of application.
- Location of sensitive areas and associated restrictions (e.g., steep slopes, drainages, buffer zones).
- Guidance forms for record keeping, equipment operations and maintenance, and a field-by-field nutrient budget for nitrogen and phosphorus applications.