The Conversion of Even-Aged Stands to Uneven-Aged Structure in Southern New England
2003
Kelty, M.J. | Kittredge, D.B. Jr | Kyker-Snowman, T. | Leighton, A.D.
Partial cutting is common in mature even-aged stands in southern New England because the level of disturbance associated with even-aged regeneration methods is unacceptable to many private owners of small forest properties. This cutting often consists of high-grading, but foresters seeking an alternative generally turn to the selection method to begin the conversion of these stands to uneven-aged structure. However, the single-tree or small-group selection methods used may produce long-term results that are similar to high-grading in shifting stand composition toward shade tolerant species (many of which have low timber value). A review was made of the extensive research on the use of the selection method in northern New England and central Appalachian forest types, as well as of the limited research in the southern New England transition hardwood-white pine (Pinus strobus)-hemlock (Tsuga canadensis) type. Recent management experience in a Massachusetts public watershed forest was also reviewed. These provide general guidelines for using selection cutting in the region to regenerate species of a wide range in shade tolerance: (a) use patch selection (rather than single-tree or group selection) with a minimum patch size of 0.3 ac, and with understory as well as overstory trees removed in the patches; (b) use area control (proportion of stand to be harvested) rather than a target diameter distribution (q-value or other method) to regulate the stand cutting level. This approach is likely to be effective in meeting regeneration goals and in being logistically feasible, given the intensity of management possible on most of these properties.
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