yicld-density relationships,such as relative density (Drew and Flewelling, 1977) or the stand density
index of Reineke (1933), can be useful tools for
assessing forest structure, by evaluating the state of
competition between trees within a stand, while also
providing information on stem density and size. Relative
density is essentially a packing ratio that relates
the mean volume of trees to the density of stems, as
a function of the self-thinning rule (Drew and