Cellulose is a difficult material to break down via microbial digestion. Considering this, then there is the problem of producing very small amounts of methane if any. Biomass gassification for wood is a better option.
Those who hammer their swords into plows will plow for those who don't!
Uh oh, we're definitely being carded. Here, show him this tiny ad:
October Rocket Mass Heater days! Wheaton Labs October 11-17