Net N mineralization was calculated as postincubation
(NH4 plus NO3) minus preincubation (NH4 plus NO3);
net nitrification was calculated as postincubation NO3
minus preincubation NO3. Other analyses at the Marshall
laboratory included organic matter (loss-on-ignition,
500°C for 5 hr) and pH (glass electrode).
Subsamples of soil originally placed in paper bags
were taken to the USDA Forest Service Timber and
Watershed Laboratory, Parsons, West Virginia. These
samples were air dried and analyzed for C and N with a
Leco CNS analyzer.
Importance values for tree species common among
silvicultural treatments were determined as a percentage
of total basal area. Personnel at the USDA Forest
Service Timber and Watershed Laboratory provided
data for tree basal area.