Modeling Missing Remeasurement Tree Heights in Forest Inventory Data

Missing tree heights are often problematic in compiling forest inventory remeasurement data. Heights for cut and mortality trees are usually not available; calculations of removal or mortality volumes must utilize either a modeled height at the time of tree death or the height assigned to the tree at a previous remeasurement. Less often, tree heights are not available for trees that were determined to be missed tally trees in an initial inventory. In these cases, a height is available for the current measurement, but the initial tree height must be modeled or estimated. In this paper, we present a procedure for predicting either a time 1 or time 2 height. The procedure uses actual tree height information for a tree collected at time 1 or time 2 if available. Incorporating the relationship between actual tree height to predicted height provides for an adjustment to height equations that do not incorporate site quality and stand parameters.