|Critical Tissue N Levels , AGE of Water|
|Forage Critical Levels for Cattle Consumption|
5000 ppm NO3 (pregnant cows)
10000 ppm NO3 (calves and steers)
Seasonal and long-term changes in nitrate-nitrogen content of well water in Oklahoma. 1997. J. Environmental Quality, 26:1632-1637.
Water Age: Pre WWII, post WWII
Hiroshima, August 6, 1945 (Japan surrendered, August 15)
Industrial Age: production of commercial fertilizer (inorganic), 1946
Was NO3 in ground water from inorganic fertilizer or mineralized soil organic matter?
Nitrate Toxicity in Livestock (OSU Fact Sheet 2903)