The Buell-Small Succession Study (BSS) comprises ten old fields adjacent to the old growth forest at the Hutcheson Memorial Forest in Somerset County, New Jersey, USA (40º30' N, 74º34'). The Hutcheson Memorial Forest (HMF), owned by Rutgers University, is composed of an old-growth forest with a Quercus-Carya canopy and a Cornus florida understory (Myster and Pickett, 1994). The soils at HMF belong to the Penn soil series, derived from the Triassic red shale of the Brunswick Formation (Ugolini, 1964).
There are only slight variations in soil texture, drainage, and depth between the ten old fields (Ugolini, 1964). In addition, there are no significant differences in nitrate, ammonium, nitrogen mineralization potential, phosphorus, calcium, potassium, soil structure, soil texture, or organic matter between fields of different ages (Robertson and Vitousek, 1981; Robertson, 1982). Consequently, it is assumed that soil differences are small between the old fields in the BSS study.
The ten old fields of the BSS exhibit four different inital conditions: the year of abandonment, season of abandonment, the last crop, and mode of abandonment as summarized in the table. The old fields also vary in size between 0.35 - 0.87 ha (Myster and Pickett, 1988). At the time of abandonment 48 permanent plots, measuring 2.0 x 0.5 m, were established on a grid in each old field. The size and shape of each field determined the placement of the grid. The permanent plots were sampled every year from 1958 to 1979, after which they were sampled every other year to the present.
Season of Abandonment: S (spring) F (fall)
Last Crop: R (row crop) H (hay)
Mode of Abandonment: B (bare soil) L (intact litter)
Myster, R. W. and S. T. A. Pickett 1988. Individualistic patterns of annuals and biennials in early successional oldfields. Vegetatio 78: 53-60.
Myster, R. W. and S. T. A. Pickett 1994. A comparison of rate of succession over 18 yr. in 10 contrasting old fields. Ecology 75: 387-392.
Robertson, G. P. 1982. Factors regulating nitrification in primary and secondary succession. Ecology 63: 1561-1573.
Robertson, G. P. and P. M. Vitousek 1981. Nitrification potentials in primary and secondary succession. Ecology 62: 376-386.
Ugolini, F. 1964. Soil development on the red beds of New Jersey. William L. Hutcheson Memorial Forest Bulletin 2: 1- 34.
The permanent plots in the Buell-Small Succession Study are sampled in late July. Typically each field is sampled by three or four teams of two people (a sampler and a recorder). Each team samples one permanent plot and the teams leap-frog over one another to insure that all plots are sampled.
Each permanent plot is outlined by laying a wooden frame around the stakes that mark the plot. The frame is placed with as little disturbance to the vegetation as possible.
The plots are sampled by estimating the percent cover of each species in the plot. If a species overhangs the plot, the percent cover overhanging is recorded. The percent cover of bare ground, litter, lichen, and moss is also estimated. Samplers start with the topmost layer, usually the trees, and work their way down to the species closest to the ground.
In addition to estimating the percent cover for trees, the number of stems of each tree species located in the plot is noted in a circle next to the cover. If the tree is located outside the quadrat no stems are counted.