Question
I have read that there are more living things in a handful of healthy soil than there are people on earth, but I can find no hard science to back this up. Is this statement true and, if it is, can you give me at least one example of a peer-reviewed study that established this fact?

Answer
Hi Tom, A gram of soil, depending on the fertility, can have from 1 milllion to 650 million bacteria.  However, bacteria are probably outnumbered by fungi, archaea and viruses according to some recent research.  The statement is true.  You should be able to find supporting documentation from many colleges.  Try Texas A&M, University of Colorado or Duke University.  I believe they all have excellent soil science departments.  Jim