Despite great contributions to the diversity of temperate deciduous forests, shrubs tend to be underrepresented in both ground layer herbaceous studies and overstory assessments.  Likewise, intermediate-stature shrubs persist in an understory forest layer of notable environmental heterogeneity. Treefalls and edge effects produce a mosaic of light availability, while substrate characteristics vary dramatically based on underlying geology, microtopography, and uprooting disturbance.  When considered with the paucity of community data, there is a considerable gap in our understanding of temperate shrub microsite specificity within temperate forest understories. Given the prevalence of gap-phase disturbance in temperate deciduous forests and the influence of soil texture on mesic forest establishment, we hypothesized that understory shrub community composition and diversity are shaped by microsite heterogeneity in light availability, soil texture, and topography. Throughout Wisconsin, 50m2 quadrats were surveyed for shrub abundance, light environment, microtopography, and soil texture analysis at sixteen mature hardwood forest sites throughout northern and southern Wisconsin. Soil cores were taken to record the depth of the A1 soil horizon as well as  ratios of sand, silt, and clay.  Light environment was characterized using hemispheric photography, while site-level climatic data was derived from 20-year averages from Wisconsin weather stations Species richness and Shannon Diversity varied fivefold between sites, though generalized linear models revealed no significant impacts across variables assessed. Composition and species cooccurrence differed greatly between northern and southern forest sites.  Multiple regression analyses of NMDS axes with a Bonferroni adjustment determined that percent clay and climatic variables significantly shape understory community composition at the site level, while quadrat level analyses show soil texture and canopy openness to significantly impact community composition. These results reveal that though climatic factors and underlying geology shape shrub community composition, the microsite composition of shrub communities is impacted by both soil texture and light availability.  Such findings highlight the importance of considering microenvironment when managing and restoring temperate understory shrub communities.