Fig. 7 Dry weight of the entire seedling (A), shoot length (B), and colonization rate of mycorrhizal fungi (C) of the tested tree species on brown rot logs, white rot logs, and soil. Different lowercase letters on the boxes indicate a significant difference across the substrates (Steel-Dwass test, P < 0.05). Ns indicate no significant differences across the three substrates (Steel-Dwass test,P > 0.05). Numbers indicate the number of replicate seedlings used for the measurements. Upper row: arbuscular mycorrhizal trees. Bottom row: ectomycorrhizal trees. Dry weight was not measured for Clethra and Betula seedlings because they were too lightweight.