Figure 1, illustrates the typical pattern of change in soil organism numbers and plant available nitrogen release from low carbon to nitrogen organic materials. Provided that soil conditions are correct for decomposition, soil organism numbers will increase when a food source (organic carbon) is added. Plant available soil nitrogen levels will also increase over time. The amount of time required for release is dependent on how easily digestible the cover crop is, and soil factors such as temperature, moisture, pH, etc. that may influence the activity of the organisms involved. The key here is to time the cover crop control date to best match the nitrogen release time with the nitrogen uptake pattern of the crop you intend to grow.

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