Silviculture Information on the World Wide Web
Research
Courses
Stand Dynamics
Quantitative Tools
Books
E-mail Lists
Online Pubs.
This page describes Silviculture information on the web.
Stand Density Index
Stand density index (SDI) is a relative measure of stand desnity the converts a stand's current density into a density at a reference size. Stand density index was present by Reineke (1933) and can be defined as:
where SDI is Stand Density index, Dq is the quadratic mean diameter. Quadratic mean diameter is the diameter of average basal area per tree. A number of maximum stand density indices have been proposed for various species. Table 1 list these stand density indices by species and source.
10-inch trees per acre. Metric units are number of 25.5cm trees per hectare.
| Species | Maximum SDI (English) | Maximum SDI (metric) | Source |
|---|---|---|---|
| White fir |
830 |
2050 |
Reineke, 1933 |
| Red fir |
1000 |
2470 |
Reineke, 1933 |
| Mixed conifer for CA |
750 |
1850 |
Reineke, 1933 |
| Douglas-fir for WA-OR |
595 |
1470 |
Reineke, 1933 |
| Douglas-fir for CA |
600 |
1480 |
Reineke, 1933 |
| Eucalyptus |
490 |
1210 |
Reineke, 1933 |
| Redwood |
1000 |
2470 |
Reineke, 1933 |
| Ponderosa Pine |
800 |
1980 |
Reineke, 1933 |
| Loblolly Pine |
450 |
1110 |
Reineke, 1933 |
| Longleaf Pine |
400 |
990 |
Reineke, 1933 |
| Slash Pine |
400 |
990 |
Reineke, 1933 |
| Shortleaf Pine |
400 |
990 |
Reineke, 1933 |
| Upland Oak |
230 |
570 |
Schnur, 1937 |
| Ponderosa Pine |
830 |
2050 |
Long, 1985 |
| Lodgepole pine |
690 |
1700 |
Long, 1985 |
| Douglas-fir |
587 |
1450 |
Long, 1985 |
| Western Hemlock |
790 |
1950 |
Long, 1985 |
| Ponderosa Pine |
450 |
1110 |
Long and Shaw, 2005 |
References
Long, J. N. 1985. A pratical approach to density management. Forest Chronicle 61:23-37.
Reineke, L. H. 1933. Perfecting a stand density index for even-aged forests. Journal of Agricultural Research 46(7):627-638.
Schnur, G. L. 1937. Yield, stand, and volume tables for even-aged upland oak forests. USDA Technical Bulletin No. 560, 87p.
Created: July 11, 2001, By David R. Larsen
Last Updated: February 7, 2007