Thinning for Browse

Abstract

Slashing for the production of browse is today a standard game management practice. In New England and New York, much of the best game range is on lands formerly in agriculture now reverting to forest. Some areas are stocked with stands in which the proportion of inferior hardwoods is undesirably high. They may result from the pioneer forest community invading grassland or from excessive cutting. Of the Northern Hardwoods, aspen, grey birch, and red maple are persistent and aggressive sprouters. When clear-cut, vigorous stumps of these species produce an abundance of coarse sprouts of low palatability. The sprouts often are 3 feet tall at the end of the first season and in 3 to 5 years grow to such size as to furnish little browse. Slashings in such stands are costly to maintain and the effect of frequently repeated cuttings upon plant succession and upon the soil is not well understood. A tract of second-growth hardwood on the writer's forest at Stephentown, New York, was marked for improvement in the fall of 1935. This area is a spring to early winter range for deer, the animals remaining until the first deep snow. The stand was 20-30 years old, with 1,000 stems per acre ranging from 2 inches to 9 inches d.b.h. By number, 35 per cent were better hardwoods (ash, red oak, sugar maple, black cherry, yellow birch) and 65 per cent were inferior hardwoods (Ostrya, soft maple, aspen, grey birch), with abundant advance reproduction of sugar maple and a scattering of small hemlock. A crown thinning, aimed to free all satisfactory trees, removed 25 per cent of the stems, chiefly grey birch and soft maple. The effect of this winter thinning upon browse production was astonishing. The additional light stimulated the growth of herbs and ferns without encouraging coarse annuals or grasses. The stumps sprouted much less vigorously than did those exposed to full sunlight. Sprouts were mostly less than 18 inches tall and much slimmer than