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Reineke’s stand density index: a quantitative and non-unitless measure of stand density

Informally Refereed

Abstract

When used as a measure of relative density, Reineke’s stand density index (SDI) can be made unitless by relating the current SDI to a standard density but when used as a quantitative measure of stand density SDI is not unitless. Reineke’s SDI relates the current stand density to an equivalent number of trees per unit area in a stand with a quadratic mean diameter (Dq) of either 10 inches (English units) or 25.4 cm (metric units). Thus, when used as a quantitative measure, SDI is in fact unit dependent on two levels, one is whether English or metric units are used, and the second is whether the unit area is 1 acre (ha) or two, three, etc. Foresters should express SDI as either number of trees per acre or /ha to clearly indicate the unit. When viewing SDI as a quantitative measure, it is legitimate to use the slope of the linear portion of an individual stand’s size-density trajectory.

Parent Publication

Citation

VanderSchaaf, Curtis L. 2013. Reineke’s stand density index: a quantitative and non-unitless measure of stand density. In: Guldin, James M., ed. 2013. Proceedings of the 15th biennial southern silvicultural research conference. e-Gen. Tech. Rep. SRS-GTR-175. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 577-579.
https://www.fs.usda.gov/research/treesearch/43690