Headwater stream invertebrate communities are strongly influenced by surrounding terrestrial environments which are, in part, governed by large-scale ecoregional characteristics and land use. Although numerous studies have investigated land use effects on aquatic biota, few have compared these effects under different ecoregional conditions. In this study, benthic and drifting invertebrate assemblages were examined from 24 headwater streams in the Wenatchee River subbasin, spanning two ecoregions. The objectives of this study were to determine 1) invertebrate community composition and abundance in headwater streams within wet and dry ecoregions, 2) how community composition varies with time after timber harvest, and 3) if the relationship between time since timber harvest and invertebrate community structure varies by ecoregion. Preliminary results suggest that within dry regions, headwater streams exposed to recent harvest have reduced density and reduced taxa richness relative to sites exposed to older harvest. Wetter regions in contrast show that headwater streams exposed to recent harvest have higher density and little change in taxa richness relative to sites exposed to older harvest. These data suggest that ecoregional conditions may govern how headwater communities respond to forest management.