Detailed crown condition information, including numbers of broken branches ≥ 5 cm diameter, broken tops, and healthy branches, were recorded for 5434 living trees > 9 cm dbh from 603 ten-basal-area-factor prism plots (three per forest stand) at 201 random points (stands) throughout the ice damage region of northern New York State. Twenty five percent of the sample stands had ≥ 20% branch breakage. Bigtooth aspen, red oak, red maple, and white pine had the most breakage. Comparison of potential mortality of trees associated with ≥ 75% ice damage (severe damage) to baseline (predicted) mortality to maintain the existing forest structure suggests that ice damage may alter the health of 18% of the forest stands but this is not sufficient to alter the health (sustainability) of the larger forest system. Key words: ice storm, forest health, sustainability, growth, mortality, dbh classes