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Whole‐tree harvesting of a northern hardwood stand in New Hampshire removed an average of 111 dry metric tons/ha of biomass, representing 96% of the aboveground total. Nutrient removal in harvested trees averaged 344, 242, 128, and 19 kg/ha for Ca, N, K, and P, respectively. The nutrients removed were between 2 and 3% of estimated total soil capital for Ca and N, and about 1% of total soil capital for K and P. Of estimated availablenutrient capital, the removals were 30% for Ca and 85% for K. The harvest was carried out on the lower 40% of a 16‐ha watershed. Concentrations of NO3, Ca, and K in soil solution and streamflow of the harvested watershed increased for 1½ to 2 years. Streamflow concentrations increased by a maximum of 3, 1, and 0.2 mg/liter for NO3, Ca, and K, respectively. Increased loss of N and Ca by leaching to streams is estimated at < 40 kg/ha. NO3in soil solution increased from background levels of 1 mg/liter to a maximum of 95 mg/liter. Ca increased from background levels of 2 mg/liter to a maximum of 19 mg/liter. Concentrations of both ions returned to background levels by the third growing season after harvest. The increases in nutrient ions in streams and soil solution are thought to result from increased mineralization and nitrification immediately after harvest. The harvested area has regenerated rapidly with pioneer and commercial species, perhaps partly because of the enriched soil solution. Nutrient removals and leaching losses by themselves do not seem to deplete total nutrient capital significantly. However, the impacts of whole‐tree harvesting upon the processes, mechanisms, and rates by which nutrients are made available for future stands are still of concern.

Dewatered and limed sludge from a primary treatment plant was applied at two rates, 25 and 125 wet metric tons/ha (5.8 and 28.0 dry metric tons/ha), on sandy loam soils in a northern hardwood forest in central New England. Changes in soil water solution were assessed from water samples collected with suction lysimeters at 20‐ and 45‐cm depths below the mineral surface. The light application of 25 metric/ha had little effect, but the heavy application of 125 metric tons/ha caused an increase in the concentration of most ions in soil water. At 20 cm, or just below the B21h horizon, Cl reached a mean maximum of 27.5 mg/liter after heavy application compared to control values of <0.4 mg/liter. Sulfate rose above mean background levels of 5.0 mg/liter to a maximum concentration of 13.5 mg/liter. Mean Ca values rose to over 13.5 mg/liter compared to background concentrations of about 2 mg/liter. Magnesium, Na, K, H, and NO3indicated maximum increases in concentration that averaged two‐ to threefold greater than control values of <0.5 mg/liter. NH4and TOTAL‐P were unchanged. At 45 cm or in the B23 horizon just above a fragipan, the increases in ionic concentrations following the heavy application were less than one‐half the increases that occurred at 20 cm. The concentrations of most ions returned to background levels within 1 year after sludge application. From the time sludge was applied in June 1975 until the end of the growing season in October 1976, leaching losses for calcium were estimated as 18 kg/ha for the control plots, compared to 39 kg/ha from plots receiving the heavy application. Comparable estimates for SO4were 35 kg/ha for the control plots and 64 kg/ha for plots receiving the heavy sludge application. There were no significant differences in basal‐area growth among control and treated plots for the first two growing seasons after sludge application. In the herb and shrub layer only 3 of the 31 commonly occurring species showed statistically significant changes in frequency. All three changes were on plots receiving the heavy application. Sugar maple (Acer saccharumF.) seedlings declined from an average of 22/m2before application to 17/m2in the second summer after application. The shrub Viburnum alnifoliumMarsh, increased from an average of 5/m2before application to 11/m2after and the herb Viola pallensBrainerd increased from 15/m2before to 21/m2after.