Sugar Maple Pigments Through the Fall and the Role of Anthocyanin as an Analytical Tool

Sugar maple habitat is projected to almost disappear in future climate scenarios. In fact, many institutions state that these trees are already in decline. Being able to detect sugar maple health could prove to be a useful analytical tool to monitor changes in phenology. Anthocyanin, a red pigment found in sugar maples, is thought to be a universal indicator of plant stress. It is very prominent in the spring during the first flush of leaves, as well as in the fall as leaves senesce. Determining an anthocyanin index that could be used with satellite systems will provide a greater understanding of tree phenology and the distribution of plant stress, both over large areas as well as changes over time. The utilization of anthocyanin for one of it's functions, prevention of oxidative stress, may fluctuate in response to changing climatic conditions that occur during senescence or vary from year to year. By monitoring changes in pigment levels and antioxidant capacity through the fall, one may be able to draw conclusions about the ability to detect anthocyanin remotely from space-based systems, and possibly determine a more specific function for anthocyanin during fall senescence. These results could then be applied to track changes in tree stress.