Find here 8 excellent recommendations to consider when harvesting forest biomass. All of them are already well established and studied and linked to useful references and citations from highly reputed scientific journals and publications.
1) Do not collect or damage large dead stems [19,20].
2) Do not remove breakable rotten stems [19,20].
3) Move and pile rotten stems if they impede operations .
4) Leave at least 2-5 bark-on down logs (such as hollow butt sections fromconifer or hardwood logs) greater than 75 .
5) Maintain ground cover, shrubs, snags, naturally regenerating tree seedlings, and other live trees important for wildlife and stand regeneration .
6) Reduce harvesting activities that disturb sensitive sites, rare species, water features and unique habitats .
7) Avoid damaging any nests .
8) Retain naturally occurring and decayed wood debris on a site .
Numbersd between rackets  are literature references.
You might found them at:
“Guidelines for harvesting forest biomass for energy: A synthesis of environmental considerations”