Fig. 2From: On the knowns and unknowns of natural regeneration of silviculturally managed sessile oak (Quercus petraea (Matt.) Liebl.) forests—a literature reviewNumber of core publications on the natural regeneration of sessile oak by evidence level (from 6 = weak to 1 = very strong) according to a ranking scheme modified after Binkley and Menyailo (2005)Back to article page