ABSTRACT An invasion by Phellodendron amurense Rupr. (Amur corktree) provided an opportunity to examine the subsequent changes in the forest composition that took place since the invasion began. Through the removal of 278 individual trees of P. amurense, tree ring analysis allowed a re-creation of the forest over the 46 yr since the species first arrived at the site. This analysis shows that P. amurense demonstrates the ability to invade additional areas and, over time, increases both its relative density and relative dominance. Through an analysis of both living and standing dead individual trees, P. amurense appears to be poised to continue its gradually increased influence over the forest. This highlights the need for better recognition of the species as an invasive plant, and a more vigorous effort to control existing invasions.