CAPABILITY ANALYSIS TO ASSESS CONFORMANCE OF DOUGLAS FIR STANDS TO CUSTOMER QUALITY SPECIFICATIONS*

Largest branch diameter in the breast-height region (LLBH) and acoustic velocity on lower bole were measured on trees in a 20-year-old Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) experiment comparing seven density management/fertiliser regimes. The less dense regimes tended to have larger mean branch diameter at breast height, with fertiliser increasing the mean even further. However, except for the densest regimes, the difference between a density regime and its counterpart with fertiliser was not statistically significant. The densest regime had significantly higher mean acoustic velocity than the other regimes, which were all the same except for one with very low velocity attributed to abnormal wood formed after damage by black bears. Although statistical significance may be lacking with respect to mean properties, subtle differences in their distributions may be important to timber sellers where purchasers often pay premiums for stands with higher percentages of trees that meet their process and customer needs. A statistica