Long-Term Ecological Research (LTER)/CDR001: Fenced Microplots (MICRO); Effects of NH4NO3 on Vegetation at Cedar Creek Natural History Area

LTER - Long-Term Ecological Research Program/Cedar Creek Natural
History Area (CDR)

LTER/CDR001 [Summary adapted from the LTER Core Data Set Catalog]:

The purpose of this experiment is to measure the effect of NH4NO3
addition on vegetation not under the stress of mammalian herbivory.
The experiment is being conducted in fields A, B, C, and D. There are
eight different NH4NO3 levels with other nutrients added to ensure
that N is the limiting nutrient, and a control which receives no
nutrients. The treatments are A, B, C, D, E, F, G, H, and I as
defined in NUTRADD.DOC in the "microplot" strategy. There are six
replicates of the nine treatments in fields A, B, and C and five
replicates in field D. The treatments were randomly assigned to the
plots except in field B where a randomized block design was used; two
blocks each half the field. In fields A, B, and C, the plots are in 6
x 9 grid and are 4 m x 4 m in size with 1 m aisles between plots. In
field D the plots are 1.5 m x 4 m in size and are placed in a 3 x 17
grid. The plots are enclosed by a fence to keep out mammalian
herbivores. To build the exclosure galvanized welded-wire hardware
cloth with 6 mm x 6 mm openings was buried to a depth of 84 cm.
Additional hardware cloth extends 60 cm above the ground, and poultry
netting extends to 1.8 m above the ground. Gophers were trapped and
removed as they appeared. Fertilizer is applied twice per year, once in early
May and once in late June.

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 (CCHNA) 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 on-line at
'http://lternet.edu/'