Soil ~> Feed ~> Manure ~> Food

We recently sent a letter to Acres regarding their article “Healthy Soils, Healthy Livestock, Healthy People”. The letter points out the relationship between the soil used to grow feed and the quality of the manure from animals eating that feed. You can read the article here : http://www.acresusa.com/toolbox/reprints/Dec05_Craine.pdf

While reading John Ikerds’ informative article on “Healthy Soils, Healthy People”, I began to wonder what might be the connection between healthy soil and “nutrient dense” manure. If food is grown on soil deficient in micronutrients it will contain fewer micronutrients. Following the process through, the manure produced by animals consuming the food grown on depleted soil will probably be deficient in micronutrients. The manure could even be more depleted than the soil the feed crop was grown on; the animal eating the food may have absorbed the last vestiges of a particular nutrient.

Many organic farms use composted manure from conventional farms as a fertilizer. What will be the long term effect on the soils of these farms? On a macro scale does this organic source have a sustainable replacement?