EQUATIONS FOR ESTIMATING LOBLOLLY-PINE BRANCH AND FOLIAGE WEIGHT AND SURFACE-AREA DISTRIBUTIONS

Equations to predict foliage weight and surface area, and their vertic al and horizontal distributions, within the crowns of unthinned lablol ly pine (Pinus taeda L.) trees are presented. A right-truncated Weibul l function was used for describing vertical foliage distributions. Thi s function ensures that all of the foliage located between the tree ti p and the foliage base is included. Foliage distribution prediction is based on actual two-dimensional foliage location. It is shown that th e average time of full foliage, and hence average foliage weight or su rface area prediction, is highly variable for loblolly pine and subjec t to considerable error. To help account for the old and new foliage d ifferences during the approximate time of ''full leaf,'' the predictio n equations for new and old foliage weight and surface area include a day-of-year term. New equations to predict branch weight, surface area , and the vertical distributions of branch biomass and surface area we re also developed, The vertical distributions of branch biomass and su rface area are described with logarithmic equations constrained to equ al zero when relative crown depth is equal to zero, and to equal one w hen relative crown depth is one.