Anatomy of red spruce needles from forest decline sites in Vermont

Abstract

Red spruce trees on upper elevation sites on Camels Hump Mountain, Vermont have shown severe decline symptoms since the mid-1960s. The anatomy of needles has been studied. Microscopic damage was seen primarily in mesophyll cells, characterized by cytoplasmic clumping and indiscernible chloroplasts. Damage increased over a single growing season and abnormal needle anatomy was found in 1985 and 1986 collections. There was a correlation of structural needle damage severity and field estimates of percentage foliar loss on low and high damage sites.