size of these aggregates is an often-debated attribute of the
small group selection forest and the limit that discriminates
between uneven-aged stands and even-aged stands, both from a
silvicultural and management point of view, is a topic of much
discussion in the academic and scientific literature (cfr. e.g.
Patrone, 1979; Smith, 1986; Bradshaw, 1992; Schutz, 1997;
Davis et al., 2001). Usually specie’s shade tolerance is
considered a determining factor in establishing the size of
the gaps (or groups) that characterize the small group selection
system.