• Yanai, Ruth D.
  SUNY-ESF
  
• Parry, Dylan
  SUNY-ESF
  
• Allen, Doug
  SUNY-ESF
  
• Lautz, Laura
  Syracuse University
  
• Carlson, Jerry
  New York State DEC
  
• Wilmot, Sandy
  Vermont DFPR
  

Sugar maple (Acer saccharum Marsh) is a keystone species of the northern hardwood forest type.  A An important stressor of sugar maple is forest tent caterpillar (Malacosoma disstria Hübner, FTC), an indigenous defoliator. The recent outbreak of FTC (2002-2007) was the largest to occur in the region in the last 50 years and affected millions of acres of forest in the northeastern U.S. and Canada.

This project had two parts.  In Part I of this project, we were interested in understanding why some sugar maple stands recover, while others decline, following insect defoliation. This research assess the condition of sugar maple trees in 47 new or previously monitored North American Maple Project (NAMP) stands in Massachusetts (2006, 2007), Vermont and New York (2007, 2008), following the collapse of the recent FTC outbreak and tested environmental factors contributing to mortality and crown dieback following defoliation. Sugar maple is known to be susceptible to decline especially on sites with low soil Ca and Mg, and we found this to be the case. Low soil K, concave site terrain shape, short-term drought, low temperatures, and defoliation were also important to sugar maple condition. User-friendly hazard rating tables were made to show which sugar maple stands were more vulnerable to decline. Land managers in the Northeast can utilize this research to assess sugar maple stands defoliated by FTC, and we suggest that fertilizer application may benefit stands with low base cations that are more susceptible to decline.