3.6
Management Guidelines
In addition to the rules and decision supporting tools for proper soil and fertility Management mentioned previously, we recommend the use of the following management practices in organic operations so as to use plant and animal materials to maintain or improve soil organic matter content in a manner that does not contribute to contamination of crops, soil or water by plant nutrients pathogenic organisms, heavy metals or residues of prohibited substances.- Animal waste should not reach surface waters by runoff, drift, manmade conveyances, direct application, or direct discharge during land application. Proper application rates and methods should be used to ensure that animal waste does not impact surface waters.
- Animal waste should be applied to meet, but not exceed, the nitrogen needs for realistic crop yields based on soil type, available moisture, historical data, climatic conditions and level of management, unless there are regulations that restrict the rate of application for other nutrients.
- Liquid waste should be applied at rates not to exceed the soil infiltration rate. In order to control conditions conducive to odor or flies, no ponding should occur.
- Manure should not be applied to saturated soils, during rainfall, or when the surface is frozen. When manure is to be applied on acres subject to flooding, it should be incorporated to the soil on conventionally tilled cropland. When applied to conservation-tilled crops or grassland, the waste may be broadcast, provided the application does not occur during a season prone to flooding.
- Manure should not be applied closer than 100 feet to wells or within 200 feet of dwellings other than those owned by the landowner. Manure should be applied in a manner not to reach other property and public rights-of-way.
- Manure should not be applied on grassed waterways that discharge directly into watercourses. If used in this situation, manure should be applied at agronomic rates and in a manner that causes no runoff or drift from the site.
- Records of waste application should be maintained to establish actual application rates. The records should include date of application, amount of waste applied per acre by tract number and field number, most recent waste analysis and soil test report, and the realistic yield expectation (RYE) nitrogen rate.
- Proper calibration of application equipment is important to ensure uniformity and accuracy of spreading rates.
- Maintaining good crop growing conditions will reduce both runoff losses and leaching losses of plant nutrients. Preventing pest damage to the crop, adjusting soil pH for optimum growth, providing good soil tilth for root development, planting suitable crop varieties, and improving water management practices will increase crop efficiency in nutrient uptake.
- Crop sequences, cover crops, and surface crop residues are useful tools for reducing runoff and leaching losses of soluble nutrients. Winter cover crops can capture residual nutrients after harvest of the summer crop. Nutrients from green manures and cover crops must be credited to determine the appropriate nutrient additions.
- Where possible, develop field borders that can serve as a nutrient trap if field runoff occurs.
- The growing of two or more crops together (intercropping) has the potential to Improve resource use. This results from differences in competitive ability for resources between above and below ground crop components in space and time.
- The influence of livestock on soil fertility and the influence of soil fertility on livestock nutrition and health are vital management considerations.
The starting point for improved soil fertility management is always the farmer.