• Piatek, Kathryn
  University of Maine
  

Tree growth characteristics can reflect stresses present in the environment. A stressed coastal site for its elevated ozone levels, acidity of frequent fog, and exposed location (wind and high light intensity). Decline symptoms on spruce trees including yellowing of needles and stunted appearance. Another site was chosen inland, where fog is infrequent and ozone levels are lower . Wind and light intensity are lower due to a closed canopy. Shoot length on the stressed coastal site is significantly lower compared to the inland sites, but the total number  of shoots per branch is greater, resulting in a similar sum of shoot lengths. Growth rate on the two sites is not significantly different; however budbreak starts later at the stressed site. The number of needles per cm is significantly higher at the stressed site; the needles exhibit sun morphology. Fresh weight and needle moisture content are significantly lower at the stressed site, but the dry weights are similar on both sites. The large tree-tree variation may mask the differences between sites. Temperature, and pollutant effects on growth are discussed.