The very little information I found while I was researching this seemed to agree with that statement. The general consensus was REPLACE THE SAND WITH SOIL. Doing a bit more reading on this site I found an old thread back from 2004, and this quote stood out to me: (http://www.lawnsite.com/showthread.php?t=61792&highlight=nematodes+price&page=2) So I guess while it may be possible for me to be able to establish and somewhat maintain a healthy lawn, in order for any organic fertilizers to contribute, I need to have a good humus layer? What are opinions on time frame to achieve such results through ammending with topdressing? could it be done within a season?