When conducting inventories, reducing variability among tree diameters, heights, and ultimately volumes or biomass, can reduce the number of points/plots needed to obtain a desired level of precision. We present a simple analysis examining the potential reduction in discounted inventory costs when stand variability is decreased (via improved genetics and intensive management on a uniform soil). Sampling time might be reduced if the coefficient of variation in point volume/biomass estimates is reduced to 10% (versus 25% for genetically diverse stands). However, if this level of variability could be achieved (and depending on the desired probability and allowable percent error) discounted costs might be only reduced by $0.50 per acre for a single inventory (when a 15% error is used). When four inventories are made across a rotation (at ages 10 to 25 years) with a goal of 5% error, total discounted savings might be $20 to $30 per acre. On some very uniform sites, stands with low variability may only need one inventory plot per 25 acres. Although clones (in theory) might reduce variability, microsite conditions within a plantation will always produce variability among plots/points.
Vanderschaaf, Curtis L.; Coble, Dean W.; and South, David B., "Increased Uniformity by Planting Clones Will Likely Have a Minimal Effect on Inventory Costs" (2012). Faculty Publications. 496.