Most farmers take soil samples and analyze the organic matter. At home, I have seen a 1% increase in organic matter since we began to go to zero tillage. It is quite incredible. Normally, you hope for an increase of 0.1% or 0.2% in two or three years, but, on my farm, I have seen an increase of 1% in 10 years.
On November 7th, 2017. See this statement in context.