Relate effects of soil, grazing intensity and burning treatments on the establishment and subsequent growth of woody plants in prairie communities and how these factors affect the prairie-forest boundary.
LOCATION OF SAMPLING STATIONS
1981: 020B, 020C, 020D, 001A, 001D, 004B, 004F, 004G, 004H, 010D, 033A, 033D, 099C
1986: 020B, 020C, 020D, 001A, 002D, 001D, 004B, 004F, 004G, 004H, 010D, 033A, 033D, 099C, N20B, N01B, N04A, N04D
1991: 001D, 002D, 004B, 020B, N01B, N04D, N20B
FREQUENCY OF SAMPLING
Beginning in 1981 and every five years thereafter.
VARIABLES MEASURED
Location of each individual tree, shrub and patch of shrubs according to species and size.
METHODS
Each area is walked in parallel lines approximately 15-20 m apart. The locations of woody vegetation are marked on a mylar overlay on a large scale aerial photograph of the area being surveyed with a unique symbol for each species and a number for size. A real effort is made to detect young individuals in order to estimate when growth started and ascertain mortality in the early years. Species are coded by symbols and color.
For trees, size is the height to the nearest meter above 2 m. For shrubs, the approximate diameter and shape of the patch is drawn on the overlay.
FORM OF DATA OUTPUT
A GIS file is prepared for each watershed and the raw ascii X,Y file coordinates are available for 1981 and 1986.