Soil temperatures and suckering response of trembling aspen (Populus tremuloides Michx.) following disposal of hog on winter-logged cutblocks

Abstract

Bark and wood residue, commonly referred to as "hog fuel" or "hog," from a portable pulp chipper was deposited on aspen cutblocks in replicated 10 x 10m treatment plots during winter logging operations in northeastern British Columbia. The treatments emulated disposal of hog under conditions that simulated on-site chipping operations. Three different rates of hog disposal were applied; 34, 68 and 102 kg m-2, and three cutblocks were treated, one each during February of 1997, and March of 1998 and 1999. We originally hypothesized that the deposition of hog would lower soil temperatures in the treated plots and reduce aspen sucker density during the following growing season. However, our observations showed an initial lag in soil warming in the treatments followed by temperature levels that rose above that exhibited in the control plots. Higher soil temperatures were correlated with greater rates of hog disposal. Increased suckering was not observed in response to higher soil temperatures and stem densities decreased as hog application rates increased.