PRESENTER NOTES

Key Discussion Topics

1.Example 1: a Nebraska 11,000 head feedlot.  Additional examples are attached at the end of the power point presentation.  Pick the example most appropriate for you audience.

2. For this feedlot, 1080 tons of nitrogen and 240 tons of phosphorus are brought onto the farm annually.  Most inputs are as purchased feeds and purchased animals.

3.For this feedlot, 430 tons of nitrogen and 120 tons of phosphorus leave the farm as managed outputs annually.  All outputs are as cattle sold for slaughter.

4.For this feedlot, the nitrogen imbalance is 650 tons annually.  Most of this nitrogen is lost as ammonia volatilization into the atmosphere.  Some excess nitrogen is added to the soil as organic and ammonium-N.   This nitrogen is in excess of what can be used by the cropping program and it is likely to transform to nitrate-N and move towards groundwater. 

References

   Lesson 2:   pages 11