An assessment of sugar maple condition following defoliation by forest tent caterpillar: Investigating soil chemistry

Sugar maple (Acer saccharum Marsh.), a keystone species of northern hardwood forests, is susceptible to decline especially on sites with low soil Ca and Mg, and is commonly stressed by forest tent caterpillar (FTC Malacosoma disstria Hubner). The recent outbreak of FTC (2002-2007) affected millions of acres of forest in the northeastern U.S. and Canada. I collected soils and assessed the condition of sugar maple trees using consecutive years of data from North American Maple Project (NAMP) stands in Massachusetts, Vermont, and New York. Mortality was highest in plots that had the most crown dieback the previous year. As expected, plots with sugar maple mortality occurred on soils with low concentrations of Ca, Mg, and K. Low soil K was the soil variable that correlated best with sugar maple crown dieback and mortality. I suggest that more attention be paid to K concentrations in soils when investigating sugar maple condition.Keywords: SUGAR MAPLE DECLINE NORTH AMERICAN MAPLE PROJECT SOIL NUTRIENT THRESHOLDS...