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People often ask whether intensively managed plantations can produce "high-quality wood" (Figure 1). We are often stymied, however, when we discuss wood quality because it is such a nebulous term and can be defined based on an infinite array of end uses and user tastes. Therefore, it is not surprising that it is hard to discuss how wood quality will be affected by different silvicultural treatments, such as rotation age, pruning, spacing, and rapid growth. It is harder still for users and mill managers to communicate in a way that lets scientists know what research is needed, and for scientists to figure out how to communicate what is already known. This note attempts to help in our conversations by separating the wood characteristics that result from the way the tree grows from the wood quality that the user demands and values. The bottom line is that wood quality is the weighted value that society gives to the wood characteristics that affect properties. We know enough to predict how intensive management will affect many wood characteristics and properties, but wood quality itself will depend on reception of the wood by the buyers and users.
To talk about wood quality, it is useful to first list the wood properties of primary importance for each of the major product groups (Table 1). Although people wearing different hats would probably include slightly different properties in this list, let us take Table 1 as a starting point for this discussion. For example, the most important properties for dimension lumber are stiffness and strength, dimensional stability, warp, and treatability. In contrast, totally different properties-gluability and compressibility-are most important for flake and strand products.
Each of the wood properties is governed by an array of biological and chemical characteristics. Again, the listing (Table 2) is somewhat subjective, but, with a little argument over definitions, it is likely that most people would agree with much of this list. What we see, for example, is that stiffness and strength are influenced by quantifiable characteristics: knots (their abundance, size, and relative positions), wood density, microfibril angle, and slope of grain. Note that log size and form are not on these lists, although they determine whether different products can even be made because of dimensional constraints.