I have finally remembered to post this chart. I'll get back to it this evening Heavily disturbed soils start at the top left and the chart moves around to the right to old growth forests. The point I have made in several posts is that the soil on a site is somewhere on this chart, lets say 1:1 for an example. If Newby sprays his Pre-M on this soil where will the succession go, backwards I would assume. How far backwards? It depends on the amount of the distrurbance. How do we measure a disturbance? Soil Bio-Assay's If we are trying to repair the biology because of a disturbance we can do that quickly by spraying compost tea, compost will attain the same goal just in much longer time frames.