The material is worthless without value-added processing. Grinding up wood slash takes labor and machinery to produce a valuable product, hog fuel  (or formerly, hogged fuel). In the bad old days of regional air pollution, chips, sawdust and other sawmill waste were burned in the iconic "teepee chip burners" which were seen everywhere in sawmill communities. Those are now banned, and more modern mills use "hogged fuel" - sawmill waste coated with used lube oil - for steam and power generation. I don't know whether the added waste oil is allowed in our local biomass electric generation plant.