Abstract
Herbaceous and woody understory layers on 5 silvicultural research plots [mainly Acer saccharum and Betula alleghaniensis] at the Upper Peninsula Experimental Forest, Michigan, were surveyed in summer for up to 5 yr after the studies began and again 50 yr later. Species composition and diversity showed the greatest change 4 and 5 yr after harvest and by 50 yr they were similar to original conditions. After 50 yr the understory was denser and had greater cover than originally. Early treatment differences among plots had diminished after 50 yr.