Treesearch

This is the sixth annual report on the pulpwood harvest in the Lakes States counties. The 1964 harvest of pulpwood in the Lakes States amounted to approximately 3.628,000 cords, 1 percent less than the all-time high in 1963. Ninety-six percent of the pulpwood production was roundwood, while the remaining 4 percent was wood residue supplied by local primary wood-using plants.

The use of artificial lights to grow tree seedlings for research and even for commercial uses is becoming common. With this has come an increasing awareness that not all types of artificial lights produce the same results (2, 3, 5). The presence or absence of particular wavelengths in the light source may cause large differences in height growth and morphological development that are separate from the effects of light intensity.

Various portions of the root systems of bigtooth aspen (Populus grandidentata) suckers were severed, and the subsequent height and radial growth of stems were measured. Aspen vegetative regeneration is heavily dependent on the parent roots for at least 25 years following initial suckering. The distal portion of the parent root contributes more to sucker growth than does the proximal. New roots at the base of suckers contribute little during the first 6 years, then become progressively more important with age, and by 25 years account for about half of annual stem growth.

The upland northern hardwoods represent a forest type of great economic, biotic and aesthetic value throughout northeastern and northcentral United States and in southeastern Canada. Sugar maple, Acer saccharum Marsh., is usually the leading dominant in these stands in terms of numbers of trees and in size. Often the economy of the areas depends largely on the lumber produced from maple. For instance, in 1954, over 54,000,000 board feet of maple were cut from 2,663,000 acres of northern hardwoods in Wisconsin alone (Horn, 1957; Stone and Thorne, 1961). In recent years, a slow decline in...

Single or repeated spring prescribed fires and single summer fires easily kill aerial stems of hazel (Corylus spp.). Although vigorous and abundant resprouting follows spring fires, resprouting is less vigorous after summer fire. Repeated summer fires destroy the ability of hazel to resprout by (1) exposing and destroying underground stem systems and (2) probably exhausting stored food reserves. A single fire may eliminate hazel if humus is sufficiently dry to be completely consumed. This drying may occur in the summer or fall, but rarely if ever in the spring.