In a 4383 ha beech forest in central Belgium, we investigated whether, within clearcuts, microclimate gradients are detectable, and we tested for correlations between plant species composition and microclimatic heterogeneity. The results highlight a strong correlation between microclimatic parameters and distance from the forest edge. Of the 47 taxa found, 38 (81%) showed a significant change in expected occurrence in response to at least one of the investigated microclimatic parameters (air and soil temperature, air humidity, light intensity). The results suggest that a substantial number of forest herbaceous species with broad European distributions show particular microclimatic requirements. Furthermore, many species show a different response to combined factors, such as for instance soil temperature with increasing air humidity, which indicates that combinations of microclimatic parameters stronger determine the actual temperature, humidity or light levels at which species are expected to be present or not.