“No, Cows Don’t Make Fertilizer,” By Steve Savage.
Fertilizer that comes from cows or other animals does not really originate with them. Manure from cows and other animals has been used as a crop fertilizer for millennia, and it is still used today for about 5% of US crop acres and for a high proportion of organic acres. It is often spoken of as an alternative to “outside inputs” for crops and as a superior option relative to “synthetic fertilizers.” … But the animals didn’t “make” any of those nutrients. For instance the ~2% nitrogen in cow manure came from whatever they ate (grass, corn, soybeans…) and those crops, except for the soybeans, were mostly fertilized with “synthetic nitrogen.” Read the full article on Science 2.0“S
Cow Manure: Not Greener than Synthetic Fertilizers
March 20, 2013
