Effects of logging and coarse woody debris harvest on lepidopteran communities in the eastern deciduous forest of North America

Expansion of biomass energy production using woody feedstocks is being accomplished through post-timber harvest removal of coarse woody debris > 10 cm. The effect of this management on forest Lepidoptera is poorly known. The present study aimed to determine whether forest lepidopteran diversity and species composition were affected by two silvicultural disturbances: timber harvest and post-logging removal of coarse woody debris > 10.0 cm in diameter. In 2014, Lepidoptera were sampled from nine forest stands subject to one of three management treatments: control (no manipulation at all), clear cut and partial retention of coarse woody debris (80% removal), and clear cut and complete removal of coarse woody debris. As expected, species richness and composition were significantly impacted by timber harvest. Subsequent removal of 80% or 100% coarse woody debris, however, did not affect specialists, detritivores and pollinators. The absence of an effect as a result of the removal of coarse woody debris could be a result of the limited number of replicate stands, small stand size and the limited range of retention treatments. We suggest, however, that retention of fine woody debris with a diameter < 10.0 cm and inclusion of unlogged stands in the forest landscape maintains some of the habitat elements necessary for Lepidoptera.