Plant aboveground biomass data: The Seasonal Effects of Nitrogen Addition in the Spring on Vegetation at Differing Times of the Growing Season

The purpose of this experiment is to measure the effect of addition of NH4NO3 in the spring on vegetation at different times during the growing season. This experiment is located within the fenced area of field C. See E001 about the construction of the fence. There are three NH4NO3 levels labeled E, G, and I as defined in fertilization details in the "microplot" category. There are 4 replicates and the treatments were randomly assigned to the 12 plots. The plots are laid out in a 3 by 4 grid and are 1.5 by 3.9 meters in area. To measure effect at different times during the growing season each plot will be sampled by clipping 0.2 m by 0.5 m quadrats every two weeks during the 1985 growing season.