  Modeling the diameter distribution of trees in forest stands is a common
forestry task that supports key biologically and economically relevant
management decisions. The choice of model used to represent the diameter
distribution and how to estimate its parameters has received much attention in
the forestry literature; however, accessible software that facilitates
comprehensive comparison of the myriad modeling approaches is not available. To
this end, we developed an R package called ForestFit that simplifies estimation
of common probability distributions used to model tree diameter distributions,
including the two- and three-parameter Weibull distributions, Johnson's SB
distribution, Birnbaum-Saunders distribution, and finite mixture distributions.
Frequentist and Bayesian techniques are provided for individual tree diameter
data, as well as grouped data. Additional functionality facilitates fitting
growth curves to height-diameter data. The package also provides a set of
functions for computing probability distributions and simulating random
realizations from common finite mixture models.
