In the majority of the most recent forest inventory reports of the various eastern states it is reported that sawtimber quality has improved since previous surveys. In many cases the portion of sawtimber logs classified as grade 1 and grade 2 logs has increased by 20 percentage points or more over the preceding eight to twelve years. In every such report it is noted that the primary cause of quality improvement is increasing average diameter and length of stems. This was noted in the 2001 State of Hardwood Resources report (Bowyer and Abt 2001) and again in this review. Luppold (2001) cautions that reports of rapidly improving quality may not reflect what is actually happening to the resource. He points out, for instance, that as much as one-fifth of the apparent increase in quality occurs in logs that have increased in size while overgrowing defects that were visible at a smaller diameter.

 

Luppold (2001) explains that reports of increasing quality may be misleading for another reason that is much less obvious. Pointing to a trend of higher proportions of maple and other mid-to-late successionary species, and lower proportions of oak and other pioneer and early-successionary species in standing timber inventories, Luppold notes that the yield of upper grades of lumber from grade 1 or grade 2 logs differs by species. Thus, a decline in the proportion of red oak and a corresponding increase in the volume of hard maple could result in a decline in the yield of upper lumber grades even if the overall proportion of grade 1 logs were to remain the same.

 

Moyle and Stier (1987) studied changes in sawtimber quality in Wisconsin following expressions of concern from sawmill operators that the quality of sawtimber was declining. Although they did find evidence of greater economic scarcity in red oak, they nonetheless found substantial increases in sawtimber volumes of red oak and of most other species, as well as increases in the proportion of grade 1 logs. Luppold et al. (1998) commented on hardwood industry assertions that quality sawtimber is becoming more scarce, even in the face of statistics showing increasing abundance of high quality hardwood. They observed that industry perceptions are usually based on attributes of specific species of timber within specific timber procurement areas whereas U.S. Forest Service statistics are based on statewide forest surveys. Thus, although they did not dispute the notion of declining availability of high quality hardwoods in particular regions, they dismissed declining hardwood quality concerns in general.