I was told by some old timers who were doing food plots before they were even called food plots, that after they worked up the soil they used a combination of free wood chips they got from the tree companies and pond dredgings to work into the soil. They said the wood chips broke down naturally and provided excellent water retention and attracted earth worms (you could also work in newsprint I would think) and the pond dredgings added micro nutrients. I have personally not done any plots so I do not have first hand knowledge. But with the abundance of good wood chips and if you could get the pond dredgings you might have an alternative to other fertilizers.