The increasing concern about the health conditions of forests in the United States and Europe 1ed to a comparative study of wood characteristics of Abies balsamea (L.) Mill. in the New England states, and Abies alba Mi1!. in the Federal Republic ofGermany. The advanced visible disease in Abies alba at several sites can be documented by means of many structural and physiological alterations. In diseased trees a suppression of the annual growth increment is obvious, and the individual transverse area of early and latewood cells decreases. The moisture content diminishes in the sapwood significantly and at the same time, wetwood deve10ps and expands into the sapwood. The element content per gram of wood does not significantly differ between healthy and diseased trees of the same stand. The content of soluble sugars increases in diseased trees, while the starch content is drastically reduced. However, parallel to the growth suppression the total amount per year of elements, soluble sugars and starch is significantly less in diseased trees than in healthy ones. In addition, accessory compounds appear to increase with the progress of disease. Cambial electrical resistance is strongly related to damage c1assification, and thereby to cambial growth.