Chemical Composition of Gypsy Moth-Killed Red Oak

With ultimate salvageability in mind, a study was undertaken to compare the chemical composition of gypsy moth-killed trees to control girdled trees. Groups of red oak (Quercus spp.) trees dead 1 through 5 years were harvested, chemically analyzed across three positions vertically in each tree including sapwood and heartwood at each location, and compared to control trees. Significant (P < 0.05) reductions in sapwood specific gravity occurred for both gypsy moth-killed and control trees. Over 3 to 5 years, sapwood was found to be either missing or showed evidence of advanced wood decay. Calorific values varied across sapwood and heartwood positions of the dead tree age groups but could not be positively correlated with time of tree death. Alkali solubility tests (1% NaOH) showed a progressive increase in extractive yield following tree death, particularly in the sapwood zone. Significant reductions in holocellulose content occurred in the sapwood zone but not in the heartwood. Klason lignin content increased slightly with time following tree death. Wood constitutent yields varied and in most cases, no systematic pattern could be established following tree death. No significant differences between gypsy moth-killed and girdled trees occurred. These results support earlier findings in that lumber losses due to biodegradation will occur shortly after tree death