Arthropods are a major component of forest biodiversity and can be indicative of forest health. I investigated the effects of forestry on spider diversity and community structure in Algonquin Provincial Park, Ontario. I found lower habitat complexity in harvested-sites accompanied by higher maximum temperatures. Spider diversity in harvested sites was characterized by lower phylogenetic diversity (PD) not reflected in species richness, abundance, nor family guilds. However, spider communities in harvested-sites were phylogenetically more clustered with higher Nearest Taxon Index (NTI). NTI was positively correlated with temperature, suggesting temperature as a possible driver of phylogenetic structure. The presence of phylogenetic signals (not detected by taxonomic or functional measures) suggests that phylogenetic measures can be a sensitive tool in detecting disturbance long after forestry has finished. Lower PD has been associated with lower ecological resilience and cautions against interpreting patterns of diversity without accounting for the impact of disturbance on phylogenetic history.