Author ORCID Identifier
Abstract
A variety of stand-density measures have become popular in North America for diagnosing thinning needs, predicting thinning outcomes, and to an increasing degree, regulating legal harvesting behavior. The statistical reliability of these measures is seldom included in the analysis, but the confidence limits of the measures must be considered if they are used in these ways. These indices are designed to measure average stocking, but conventional approaches do not address issues of stand heterogeneity. If the variability of the sample estimates is calculated in order to determine statistical reliability, it is then tempting to use that variability to address two questions, both of which relate to the degree of clumping or regularity in the spatial distribution of trees. The first question concerns the variability in competitive environment experienced by individual trees, and arises naturally in diagnosing thinning needs and predicting thinning outcomes in heterogeneous stands. The second question concerns the fraction of the stand area that is above or below a density threshold, and arises naturally in planning treatments and in law enforcement actions. We show that the ability to answer both types of question depends on the inventory method used (plot or prism) and its implementation (plot size or basal area factor, edge correction, and sampling design). These impacts must be considered in operational assessments of heterogeneous stands, and in designing enforceable forest harvesting regulations.
Date Created
September 9, 2001
Department
Natural Resources and the Environment
Publication Date
2001
Subject
Quantifying Forest Density and Competition
Language
English
Medium
CD-ROM
Digital Object Identifier (DOI)
None at present. Would like to obtain a DOI.
Document Type
Article
Source
Thinnings: A Valuable Forest Management Tool. Proceedings of an IUFRO Conference, Quebec City, Quebec, September 9-14, 2001.
Recommended Citation
Ducey, Mark J. and Larson, Bruce C., "On Parsing the Within-Stand Variability in Stand Density Measures" (2001). Faculty Publications. 2470.
https://scholars.unh.edu/faculty_pubs/2470