Animal waste levels are calculated based on: (1) animal population data compiled in the 1997 Census of Agriculture; and (2) animal waste factors from the North Carolina Agricultural Chemical Manual. Because each source has its own system for categorizing animal types, certain assumptions are needed to carry out the calculations.
SCORECARD CONSIDERS UNSPECIFIED CATTLE TO BE CALVES
The 1997 Census of Agriculture primarily breaks cattle into two categories-- beefs cows and dairy cows, each of which has individual waste factors that were used in its animal waste calculations. However, most counties had a total population of cattle and calves that was larger than the sum of beef cows and dairy cows. In these cases, Scorecard considered unspecified cattle to be calves, and derived a separate calves waste factor. The calves waste factor is the average of the beef cows and dairy cows factor, normalized to reflect that calves weigh much less (note that the average weight for a calf is 300 pounds, for a beef cow is 800 pounds, and for a dairy cow is 1400 pounds).
SCORECARD CONSIDERS UNSPECIFIED POULTRY TO BE LAYER HENS
For the 1997 Census of Agriculture data, Scorecard used a weighted average of the layers and broilers waste factors for chickens older than 3 months that were not hens.