30 Years of Nitrogen Fertilization in Spruce-Fir Forest

Rocks and sediments bind up almost 98 percent of all nitrogen. The remaining 2 percent is in motion, part of a global chemical cycle that includes humans, bacteria, plants, and the atmosphere. “Plants need nitrogen to grow,” says U.S. Forest Service research ecologist Steve McNulty. “However, excess nitrogen can harm plants.” Nitrogen and sulfur can…  More