Red Spruce Makes a Comeback (IMAGE) USDA Forest Service - Northern Research Station Caption Scientists with the USDA Forest Service and the University of Vermont found that reduced inputs of acid rain and warmer temperatures in the fall, winter and spring are factors in a resurgence of red spruce trees in the Northeast. Credit Alexandra Kosiba, University of Vermont Usage Restrictions credit the photographer License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.