PREDICTING INTERNAL YELLOW-POPLAR LOG DEFECT FEATURES USING SURFACE INDICATORS

Determining the defects that are located within the log is crucial to understanding the treeAog resource for efficient processing. However, existing means of doing this non-destructively requires the use of expensive X-raylCT, MRI, or microwave technology. These methods do not lend themselves to fast, efficient, and cost-effective analysis of logs and tree stems in the mill. This study quantified the rela-tionship between external defect indicators and internal defect characteristics for yellow-poplar logs. A series of models were developed to predict internal features using visible external features, log diameter, indicator width, length, and rise. Good correlations and small prediction errors were observed with sound (sawn), overgrown, and unsound h o t defects. For less severe defects such as adventitious budslclusters and distortion type defects weaker correlations were observed, but the magnitude of prediction errors was small and acceptable. Keywords. Yellow-poplar, hardwood log, defect modeling, internal defect prediction, external indicator. INTRODUCTION ing internal log information, an inexpensive and One of the major emphasis areas today in hardwood research is the development of equip