Aaron R. Weiskittel 
,
Laura S. Kenefic,
Robert S. Seymour,
Leah M. Phillips
Long-term effects of precommercial thinning on the stem dimensions, form and branch characteristics of red spruce and balsam fir crop trees in Maine, USA
Weiskittel A. R., Kenefic L. S., Seymour R. S., Phillips L. M. (2009). Long-term effects of precommercial thinning on the stem dimensions, form and branch characteristics of red spruce and balsam fir crop trees in Maine, USA. Silva Fennica vol. 43 no. 3 article id 196. https://doi.org/10.14214/sf.196
Abstract
The effects of precommercial thinning (PCT) on stem dimensions, form, volume, and branch attributes of red spruce [Picea rubens Sarg.] and balsam fir [Abies balsamea (L.) Mill.] crop trees were assessed 25 years after treatment in an even-aged northern conifer stand. Treatments were a uniform 2.4 x 2.4-m spacing and a control (no PCT). The PCT treatment significantly increased individual tree diameter at breast height (DBH), height growth, crown ratio, and crown width, while it reduced the tree height to DBH ratio. PCT also significantly increased stem taper and consequently, regional volume equations overpredicted observed stem volume by 2 to 15%, particularly for the spaced trees. PCT also increased the number and maximum size of branches on the lower bole. The sizes of knots on half of the sampled spruce crop trees in the spaced plots precluded them from being used as select structural lumber; there were no other effects on log grade. Our findings indicate that PCT can have a long-term influence on the structural attributes of individual trees, and that improved stem-volume prediction equations are needed in the Acadian region of North America.
Keywords
Acadian Forest;
growth and yield;
Abies balsamea;
Picea rubens;
precommercial thinning
-
Weiskittel,
School of Forest Resources, University of Maine, Orono, ME 04469, USA
E-mail
aaron.weiskittel@umit.maine.edu
- Kenefic, U.S. Forest Service, Northern Research Station, Bradley, ME 04411, USA E-mail lsk@nn.us
- Seymour, School of Forest Resources, University of Maine, Orono, ME 04469, USA E-mail rss@nn.us
- Phillips, School of Forest Resources, University of Maine, Orono, ME 04469, USA E-mail lmp@nn.us
Received 2 June 2008 Accepted 8 June 2009 Published 31 December 2009
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Available at https://doi.org/10.14214/sf.196 | Download PDF
