Tree Growth Form and Site-quality in the Eastern U.S.: A Checkup on the Health of Our Forests

Tree growth form in old-growth forests will be compared with second-growth forests throughout the eastern U.S. Silviculture is a long-term experiment, and the best scientific way to see its impact on the forests is through periodic comparisons with old-growth forests that serve as controls (in addition to the many other reasons for setting them aside). Land clearing during European settlement of the eastern U.S., along with one to three centuries of highgrading, could have put many eastern forests through a bottleneck whereby productivity has been reduced through site degradation, loss of genetic diversity, or simplification of the ecosystem. Here we propose to do a range-wide check of the current status of several important eastern tree species.

Tree height has historically been one of the most important factors that determine stand productivity. Tree height is also susceptible to decline over time. If biologically intact old growth stands on equivalent landforms and geographic locations have taller trees, that may indicate that such stands may have genetic and/or site superiority. Tree height is strongly influenced by genetic factors and it has been found that some of our species of interest are likely to lose genetic variability if too few trees are left after harvest. Therefore, a comparison of tree heights in old-growth stands with those of heavily human influenced second-growth stands seems a reasonable approach.