Estimating Defoliation of Hardwoods Using Blade-petiole Relations

摘要

Prediction equations for estimating leaf blade area and dry weight from measurements of petiole thickness were used to estimate defoliation of Populus tremuloides, Acer rubrum, Quercus rubra, and Q. alba. On one tree of each species, a sample of leaves was artificially browsed in May and harvested in July. The fractions of leaf blade tissue remaining in the samples after treatment in May were compared to the fractions remaining after harvest in July, which were calculated using the blade-petiole relations. Significant differences were found between the fractions for all species except P. tremuloides. Late browsing treatments were applied to leaf samples of the same trees in July.