After the Oea, 0-10 cm mineral and 10-15 cm mineral soils were passed through a 5.6 mm sieve (see Methods for 1991 soil sampling), the roots were picked out and separated into three categories. Two of the categories were fine tree roots and woody tree roots. The third category for the Oea soils was "tubers etc."roots (mainly Mianthemum canadense). The third category for the 0-10 cm soils was "herb" (herbaceous) roots, and for the 10-15 cm soils the third category was designated "other" roots. Roots were rinsed in reverse-osmosis quality water and dried at 70 °C and weighed.

Data were initially expressed as g oven-dry roots per surface area of soil, for each of the depths sampled. Oea data were calculated using a surface area of 225 cm², the area of the 15 cm x 15cm template. Mineral soil calculations used an area of 20.78 cm2, the area of a 2" diameter core. These values were then scaled up and expressed as kg oven-dry roots per hectare.

Data:

Tree fine = fine tree roots
Tree woody = woody tree roots
Herb = herbaceous roots (0-10 cm mineral soils only)
Tubers = tuberous roots (Oea soils only)
Other = roots not in fine tree or woody tree categories (10-15 cm soils only)
Avg = mean root mass per plot, category, and depth//horizon, expressed as kg/ha
se = + 1 standard error of the mean, calculated as: [standard deviation (sample) of the mean /square root of n]
n = number of samples
trt = treatment (if given)
blk = block (if given)