I came across this video -- just sharing -- 
 
 This garden was built mainly from wood chips. 
 The method used to break them down and build the soil 
 was with azomite rock dust and mushroom spores and white cap mushrooms
 
 
http://www.youtube.com/watch?v=MEkFFRjDkvs
 
 The caution always is... to get wood chips from clean, unsprayed wood 
 and to use the chips as mulch rather than mixing into the soil. 
 She also talking about how minerals revived her old apple tree.