Improvement In Butt Log Grade With Increase In Tree Size For Six Hardwood Species

S2Work carried out by the Northeastern Forest Experiment Station in West Virginia in the past 12 years provides useful information about the relationships between tree d.b.h. and butt-log grade. The upper logs are not included in the relationships. Being smaller and containing more knots, these upper logs are generally of lower grade than the butt logs. Thus the average grade of all material in the sawlog portion of the tree is generally lower than the average grade of the butt log. In the West Virginia data, species differences in d.b.h.-grade relationship are readily apparent. This inherent tendency for species to have different proportions of the various grades in logs of the same size is a familiar phenomenon to grade-conscious foresters who work with hardwoods. The results in this paper provide a quantitative evaluation of this tendency for six of the local species.S3.

S2Describes the distribution of sawtimber trees by diameter at breast height (d.b.h.) and grade for eight hardwood species in upland oak stands of Pennsylvania. The proportion of trees by d.b.h. and grade revealed differences between species. The quality of northern red oak, white oak, and yellow-poplar appeared inherently better than that of red maple, chestnut oak, and a group of other hardwoods. Grade predictions by size and species allow more precise timber appraisals and enable managers to evaluate alternative management strategies more accurately. S3.