The disease affects nearly every beech tree in the Catskills, and it is especially prevalent in the mid-elevation forests (Griffin et al 2003). One of the effects of the disease has been a reduction in the Catskill's beech population, resulting in an increase in beech's major competitor, sugar maple. We have studied a sequence of stands that range from healthy mixed beech-maple forest to stands where once-dominant beech trees have succumbed to beech bark disease and been replaced by maples. We have found that as the disease progresses and the beech are replaced by sugar maple, there are associated changes in carbon and nitrogen cycling such as increased soil respiration, increased litter decomposition, and increased nitrate production (Hancock et al. 2008, Lovett et al. in press).
We are also studying several hundred plots in the Catskills of New York and the White Mts. of New Hampshire to understand the tree species change caused by the beech bark disease and its implications for carbon storage and nitrogen retention in the forest.