From the USFS - a few docs about felling safety and hazard trees.
www.ventanawild.org/downloads/scratchline_issue16.pdf
www.ventanawild.org/downloads/scratchline_issue17.pdf
www.ventanawild.org/downloads/tree_strikes_you.doc
www.ventanawild.org/downloads/felling_safety.doc
www.ventanawild.org/downloads/hazard_tree_briefing.doc
dbk