Coarse Woody Debris. Dead pieces of wood including downed, dead tree and shrub boles, large limbs, and other woody pieces that are severed from their original source of growth or are leaning more than 45 degrees from vertical. For decay classes 1-4, CWD transect diameter must be 3.0 inches (7.6cm), for decay class 5 the transect diameter must be 5.0 inches (12.7 cm).