Skip to Main Content
Stand density index in uneven-aged ponderosa pine standsAuthor(s): C.W. Woodall; C.E. Fiedler; K.S. Milner
Source: Can. J. For. Res. 33: 96-100 (2003)
Publication Series: Scientific Journal (JRNL)
Station: North Central Research Station
PDF: Download Publication (407.12 KB)
DescriptionStand density index (SDI) was developed to quantify relative stand density in even-aged stands. Application of SDI in uneven-aged stands has been described mathematically but not justified biologically. Diameter-class trends in SDI and sapwood area across 14 uneven-aged ponderosa pine (Pinus ponderosa Dougl. ex P. & C. Laws.) stands in eastern Montana were examined to elucidate the biological underpinnings of the SDI summation method. Results indicate that the SDI summation method is biased in its apportionment of relative stand density across diameter classes in uneven-aged ponderosa pine stands. SDI apportions greater relative density to small trees than to larger ones. Therefore, SDI may overpredict site occupancy for reverse J-shaped diameter distributions with more small trees than large ones, and it may underpredict occupancy with nonreverse J-shaped diameter distributions. Application of the SDI summation method in uneven-aged ponderosa pine stands may be biologically justified only if site occupancy - diameter class trends are taken into account when interpreting SDI values. Replacing the self-thinning scaling factor of the SDI summation method with more biologically relevant scaling relationships may create improved relative density measures for uneven-aged stands.
- Check the Northern Research Station web site to request a printed copy of this publication.
- Our on-line publications are scanned and captured using Adobe Acrobat.
- During the capture process some typographical errors may occur.
- Please contact Sharon Hobrla, firstname.lastname@example.org if you notice any errors which make this publication unusable.
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationWoodall, C.W.; Fiedler, C.E.; Milner, K.S. 2003. Stand density index in uneven-aged ponderosa pine stands. Can. J. For. Res. 33: 96-100 (2003)
KeywordsPonderosa pine, (Pinus ponderosa Dougl., Montana, stand density index, site occupency
- Susceptibility of ponderosa pine, Pinus ponderosa (Dougl. Ex Laws.), to mountain pine beetle, Dendroctonus ponderosae Hopkins, attack in uneven-aged stands in the Black Hills of South Dakota and Wyoming USA
- Intertree competition in uneven-aged ponderosa pine stands
- GENGYM: A variable density stand table projection system calibrated for mixed conifer and ponderosa pine stands in the Southwest
XML: View XML