Whole-farm nutrient balances are an important tool for
California dairy farms Alejandro R. Castillo, UC Cooperative
Extension California Agriculture 63(3):149-151. DOI:
10.3733/ca.v063n03p149. A.R. Castillo is Dairy Science Farm
Advisor, UC Cooperative Extension, Merced County; In terms of
nutrient balances, modern dairy systems are more complex than
ever before. Feed is the primary nutrient input on the average
California dairy farm. Whole-farm nutrient balances are an
important tool for evaluating the economic and physical
viability of each dairy farm, improving nitrogen imbalances and
complying with environmental regulations. This article discusses
the concept of nutrient balances and variables affecting the
improvement of nitrogen imbalances in California dairy systems.
In May 2007, California's Central Valley Regional Water Quality
Control Board (Region 5) adopted new regulatory waste-discharge
requirements for all existing and new milk-cow dairies in the
Central Valley (CRWQCB 2007). Dairy farmers were