Coarse Downed Wood Monitoring stocks of coarse downed wood (CDW) is important because CDW uniquely influences ecosystem function. There are two components to the sampling design that are required to accurately estimate CDW mass: volume estimation and calculation of bulk density. NEON employs a tally-based method of CDW sampling as well as wood bulk density sampling. Bulk density sampling is measured by cutting cross-sectional disks from a statistically sufficient population of CDW particles, then determining the mass and volume of the disk samples. Tally sampling at SRER occurs once every three years within all Tower Plots (n=18) and a subset of Distributed Plots (n = 20). Density sampling occurs at those same plots once within three years of sampling and one more time during the life of the site.