Reaction Wood in Pinus taeda—A Preliminary Report

Abstract

Excessive compression wood has been reported from most young Pinus taeda stands in the summer rainfall region. Huge financial losses are predicted and the Forestry Branch of the Department of Environment Affairs has stopped planting the species until the probability of incidence has been markedly reduced. Climate, site and silvicultural practices do not appear to be causative. An inherited susceptibility in certain seed orchard families has been found which usually coincided with susceptibility to black pine aphid (Cinara cronartii) infestation. The most susceptible families have been removed from the seed orchards and attempts are being made to get the black pine aphid under biological control.