Skip to main content

A Nonlinear Timber Yield Equation System for Loblolly Pine

Buy Article:

$29.50 plus tax (Refund Policy)


A system of equations for predicting current and future stand volumes and future stand densities for two merchantability classes--merchantable and sawtimber--is presented. The familiar modified Schumacher yield equation was used for the stand volume functions, and a modified form of the Chapman-Richards growth model was used for stand density projection. The procedure for modifying the Chapman-Richards function can be used to derive other functional forms with stand age as a variable. Because some of the equations are intrinsically nonlinear and the residuals are probably both contemporaneously and temporally correlated, joint generalized nonlinear least squares were used to estimate the parameters. The resulting system retains the advantages of a whole stand model while providing better estimates through the use of additional stand density information. Forest Sci. 29:582-591.

Keywords: Mathematical models; growth and yield; seemingly unrelated nonlinear regressions; statistical analysis

Document Type: Journal Article

Publication date: 1983-09-01

More about this publication?
  • Forest Science is a peer-reviewed journal publishing fundamental and applied research that explores all aspects of natural and social sciences as they apply to the function and management of the forested ecosystems of the world. Topics include silviculture, forest management, biometrics, economics, entomology & pathology, fire & fuels management, forest ecology, genetics & tree improvement, geospatial technologies, harvesting & utilization, landscape ecology, operations research, forest policy, physiology, recreation, social sciences, soils & hydrology, and wildlife management.
    Forest Science is published bimonthly in February, April, June, August, October, and December.

    2015 Impact Factor: 1.702
    Ranking: 16 of 66 in forestry

    Also published by SAF:
    Journal of Forestry
    Other SAF Publications
  • Submit a Paper
  • Membership Information
  • Author Guidelines
  • Podcasts
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free ContentFree content
  • Partial Free ContentPartial Free content
  • New ContentNew content
  • Open Access ContentOpen access content
  • Partial Open Access ContentPartial Open access content
  • Subscribed ContentSubscribed content
  • Partial Subscribed ContentPartial Subscribed content
  • Free Trial ContentFree trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more