Differences in forest area classification based on tree tally from variable- and fixed-radius plots

Abstract

In forest inventory, it is not enough to formulate a definition; it is also necessary to define the “measurement procedure.” In the classification of forestland by dominant cover type, the measurement design (the plot) can affect the outcome of the classification. We present results of a simulation study comparing classification of the dominant cover type between fixed- and variable-radius plot designs. We also show the effect of species distribution and partially sampled plots on these classifications. Plot type, area sampled, and the way in which the species are distributed influence the outcome of the classification. Thus, estimated changes in forest area may be an artifact of plot design changes, rather than actual population change.