Predicting measures of diversity for forest regeneration using site and overstory variables: A regression approach

To create more timely estimates of understory woody plant characteristics, we developed a model suitable for predicting diversity in the understory of forested stands from commonly collected overstory information. We used individual measures of species abundance and species distribution as well as two diversity indices that combine the two aspects of species diversity. The objectives of this study were to (1) collect site, overstory, and understory information as part of a comprehensive forest inventory, (2) calculate overstory parameters and understory diversity measures, and (3) develop a regression model suitable for predicting ecological diversity measures of the woody understory based upon site and overstory information. Variables relating to physical site characteristics and stand attributes were shown to explain up to 65% of the variability when predicting measures of woody understory species diversity. Density of trees ≤15 feet tall appeared in all four models and was negatively correlated in each case.