This long-term experiment in Maine, U.S.A., was designed to provide information on the best silvicultural practices for managing stands of mixed northern conifers in northeastern U.S.A. We evaluated growth and yield and changes in species composition, quality, and structure during the first 40 years of the experiment. Replicated treatments include the selection system, uniform shelterwood, unregulated harvesting, and diameter-limit cutting. The new cohort established under three-stage shelterwood was subsequently left untreated or precommercially thinned. Between-treatment differences in net volume growth were not significant (α = 0.10), though gross volume growth differed significantly for managed vs. unmanaged, selection vs. shelterwood, and shelterwood vs. diameter-limit treatments. A three-stage shelterwood method with precommercial thinning 10 years following final overstory removal resulted in good control of hardwoods and hemlock and a dramatic increase in spruce and fir. The selection system on a 5-year cutting cycle resulted in increased hemlock, spruce, and fir, with a decrease in hardwood species. If the primary goal were production, even-aged management would most likely be preferred. We recommend a two-stage shelterwood method as applied in this experiment with some modification to improve species composition and stand quality. Stand quality (proportion of stand volume in cull trees) and species composition was influenced by treatment.

An experiment described in this article is used to illustrate how laboratory experimentation can be an efficient and managerially useful information source. Procedures to assess the validity of a laboratory experiment and considerations of the role of laboratory experimentation in a research system that employs both lab and field environments are discussed.

Three individual-tree selection harvests over a 48 yr period in a northern hardwood stand in New Hampshire resulted in an increase in the percentage of volume in trees with grade 1 and 2 butt logs from 21% (1952) to 30% (2000) in beech and 40% (1952) to 65% (2000) in sugar maple and other hardwoods. By 2000, 90% of the volume was in tolerant species.

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Examines the effect of sale characteristics and number of bidders on sale value for timber sold by sealed-bid auction on the Green Mountain National Forest in Vermont. As anticipated from theory and previous empirical studies, increasing the number of bidders tended to increase the winning-bid value for the timber auctions studied. Tobit analysis was used because of the high number of timber sale offerings that received no bids. Efforts made to ensure that an offering received at least one qualified bid had a greater impact on sales revenue than efforts made to increase the high-bid value. In designing sales, managers should avoid setting appraisal value too high in relation to timber quality or should seek methods other than timber sales to regenerate poor quality stands.