Long-Term Ecological Research (LTER)/CDR018: Plant Competition Under Different Nitrogen Levels at Cedar Creek Natural History Area

Thus, there are no replicates of a treatment within a soil mixture. Rather, the experiment is a regression experiment, with the regression variable being the experimentally imposed level of total soil nitrogen. At the time the seeds were planted, each plot was fertilized with a mixture of P, K, Ca, Mg, and trace metals.

Plots 1 through 23 were planted with different combinations of the following species: Schizachyrium scoparium, Andropogon gerardi, Bouteloua gracilis, Panicum virgatum, Agropyron smithii, and Buchloe dactyloides. A belowground gopher fence and an aboveground rodent/deer fence was built around the area. Proprietary limits: Investigators have priority over data for five years, but are interested in collaboration for novel comparisons before then.

The Cedar Creek Natural History Area (CCNHA) is a 2200 hectare experimental ecological reserve operated by the University of Minnesota in cooperation with the Minnesota Academy of Sciences. CCNHA is located in Anoka and Isanti Counties north of Minneapolis/St. Paul.

The site was established in 1940, was designated a National Natural Landmark by the National Park Service in 1975. In 1977 it was included as an Experimental Ecology Reserve in a proposed network, and in 1982 it was one of 11 sites in the U.S. selected by the National Science Foundation for funding of LTER. Information about LTER is also available at 'lternet.edu/'