Abstract
Abstract
We evaluated height and diameter growth of 19 sugar maple (Acer saccharum Marsh.) and 20 American beech (Fagus grandifolia Ehrh.) saplings in a 22 ac northern hardwood selection system stand cut in Fall 1973 to a residual density of 73 ft²/ac, and again in Summer 1993 to 82 ft²/ac. We classified the sample trees according to the proportion of total age represented by the 19 yr period after the 1973 selection cutting: more than 80% (young trees), 67–80% (intermediate trees), and less than 67% (old trees). Young trees reached 1 in. dbh almost one decade sooner than old trees (25.7 vs. 33.8 yr), but the two age groups did not differ significantly in height when they reached that threshold diameter. Young and intermediate-aged trees grew more rapidly in height than older trees, especially during the first 10 yr after cutting (6.1 vs. 4.9 ft during the 10 yr period). Height growth of saplings for the last 9 yr of the first cutting cycle did not differ significantly from that prior to the first cutting (2.4 ft in 5 yr), but differed from the growth during the first 10 yr after the 1973 cutting (2.85 ft in 5 yr). Young trees also took 33% less time to reach 1 in. dbh during the first cutting cycle. Findings show the influence of single-tree selection cutting on the development of small trees, and highlight the importance of matching residual density and cutting cycle length in order to maintain good rates of height and diameter growth among young age classes in uneven-aged selection system stands. North. J. Appl. For. 17(4):149–152.