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Abstract
The two age system uses methods or treatments which retain a limited number of older canopy trees (reserve trees) along with a cohort of younger regenerating stems. Methods such as “irregular shelterwood” or “shelterwood with reserves” developed from treatments such as deferment cuts can be used successfully in many hardwood stands. This method has been used as an aesthetic alternative to clearcutting and as a means of potentially developing a limited number of large diameter high value sawtimber trees in a stand. A shelterwood with reserves differs from a traditional shelterwood in that reserve trees will be maintained for a second rotation length rather than removed after regeneration goals have been met. To allow for continued rapid development of the younger age class the reserve trees must be scattered and few in number (10-30 ft2 of basal area a-1). In this case, the term shelterwood with reserves is misleading as the goal is not to shelter or modify regeneration but to allow it to develop relatively unhindered. The reserve trees must be of proper vigor, landscape position, species, age, and potential tree grade so that they will survive and provide a viable product after two rotations. Not all stands and species can be managed using the two age system. Species which are relatively long lived and are commercially important make good candidates for reserve trees.
Parent Publication
Citation
Stringer, Jeffrey W. 1999. Development of advanced oak regenerartiion from two-age reserve trees. In: Stringer, Jeffrey W.; Loftis, David L., eds. 1999. Proceedings, 12th central hardwood forest conference; 1999 February 28-March 1-2; Lexington, KY. Gen. Tech. Rep. SRS-24. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 293 p.
