"Manure is nitrogen rich, which makes it a great fertilizer. But by applying every last bit of ma nure to their fields, California dairy farmers—and non-dairy farmers as well—are dosing their crops with more nitrogen than the plants can absorb. The excess nitrogen is causing serious air and water pollution problems and may even be threatening the health of the soil."

Stephanie Ogburn reports for Grist February 19, 2010. [2]