The purpose of this observational study is to describe the dynamics of
ecosystem succession. This is done via periodic resampling (approximately
every 6 years) of permanent plots distributed across a chronosequence
of more than 20 fields of differing successional ages. Fields are sampled
for soil nutrients, (in particular, nitrogen) abundance of vegetation,
species composition and herbivore populations. In the initial survey,
100 quadrats of size 1 by 0.5 m were sampled per field in 23
different fields. Abandoned fields included in E014 are 4, 5, 10, 21,
24, 26, 27, 28, 32, 35, 39, 40, 41, 44, 45, 47, 53, 70, 72, 76, 77. Fields
22(B), 29(A), and 69(C) were originally included in E014 but used for other
purposes shortly after the start of the study. Permanent transects are
marked for purposes of sampling in a consistent location from year to year.
This experiment was established in 1983 and 1989 by principal investigators
Johannes Knops and David Tilman.