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Two perennial problems in the management of uneven-aged forests are considered: (i) determination of the optimal sustainable distribution of trees by diameter class, i.e. stand structure, for a given initial stocking level, and (ii) the optimal cutting schedule for the conversion of an irregular stand to a target structure. It is shown, using examples for northern hardwood stands in Wisconsin, that both problems can be solved via mathematical programming techniques. The programming approaches utilize a set of nonlinear equation models for stand table projections which consider the interdependence of size classes within the stand. To illustrate procedures, optimal stand structures are found for a case where initial stand basal area is constrained to specified levels and the objective is to maximize value growth over the cutting cycle. A conversion cutting schedule is then determined for a case in which the objective is maximization of present worth. It is emphasized that both the optimal distribution and conversion problems can be generalized to consider a broad range of objective functions, lengths of cutting cycle, and constraints on the growing stock.

Nova Scotia's legislation regulating operation of privately owned forests is a progressive step but it has three disadvantages:1. It is discriminating against owners of large holdings. Public regulation should be applied to all properties, with the possible exception of farm woodlots.2. Forest taxation, long inequitable in this Province, is made even more so by this Act. Taxes should be reduced on properties where satisfactory forestry is practised.3. Although selection cutting is highly desirable, cutting softwoods 10 inches and up will be followed by extensive windfall in most stands.The writer is in favor of state regulation, provided regulations are equitable and economical.

After a 6-year calibration, four watersheds in the Fernow experimental forest in West Virginia were logged during 1957–1958. Practices ranged from a commercial clearcutting with ‘logger's choice’ skid roads to a light selection cutting with planned skid roads on moderate grades. For the most part, the treatments did not seriously disturb the forest floor. Annual flow increased up to 5 area-inches on the clearcut watershed the year after treatment. Increases fell into a logical pattern with volume cut. Most of the increase came in the growing season; from May to October 1959, increases were 3.0, 1.8, 1.4, and 0.3 area-inches for per-acre cuts of 8.5, 4.2, 3.7, and 1.7 thousand board feet, respectively. Low flows were augmented, especially for the two heavily cut watersheds. Effect on high flows was variable; on the clear-cut watershed some storm-period flows in the growing season were more than doubled, whereas some snow-melt flows were less than expected. Care in the logging operation was clearly reflected in water quality; maximum turbidities ranged from 56,000 ppm on the watershed having unplanned skid roads and no provision for drainage to 25 ppm on the watershed having carefully planned skid roads. Effects of treatment are diminishing with passage of time.

"Selective cutting" does not appear in any forestry terminologies and has been used so loosely as to be almost devoid of meaning. Its abandonment is recommended. However, many foresters equate it roughly with selection cutting and all-aged forestry. The merits of selection cutting are discussed, and the writer concludes that it is unsuitable for extensive use in forests of spruce and fir in the Maritimes and adjacent regions.

A number of disease considerations are discussed as they relate to clear-cutting, selection cutting, and maintaining pure stands of lodgepole pine in Alberta.

A stand of northern hardwoods located in the Adirondacks Mountains (N.Y.) was studied in regards to structure, composition, and development. The stand has been exploited in the past by selection cutting but during the last 40 years has remained practically undisturbed. Eighteen tree species contribute to the composition of the stand within the 4 acres studied; the most abundant are Fagus grandifolia, Acer saccharum, and Tsuga canadensis. The forest mixture is made up of single trees of small groups of trees of the same species. Stand structure is typically uneven—aged even in small areas, showing characteristics of selectively cut forests, though the frequency—dbh distribution examined separately for Quercus borealis, Betual lenta, and Betula papyrifera is of the even—aged type. There is abundant regeneration of Fagus gradifolia, Ostrya virginiana, and Acer saccharum, and the forest is slowly changing to an increasing predominance of tolerant species. Good correlation between diameter and age exists for F...

Stand development on 100 acres of fir-spruce-birch forest being converted from a three-age-class structure to an uneven-aged one suitable for selection management is discussed. Periodic fellings were made in 1947, 1956, and 1966 and although the forest as a whole now has an uneven-aged structure, there are only a few small areas of true selection forest. Growth of merchantable wood has increased over the past 10 years and is now 0.9 cord/acre per annum; this is slightly higher than the growth on an adjacent commercial clear-cut (1947) but the standing volume on the clear-cut is higher.It is suggested that the selection system might be suitable for smaller companies and for woodlot owners.