| Summary: | With the information presented in this paper, obtained from the technical literature, it is proved that shrinkage of wood can be explained partially from the lignin content. Temperate hardwood species, both from México and the United States undergo a greater shrinkage percentage than tropical hardwoods and softwoods from both countries. The three-dimensional stiffness of lignin, greater than that of the other chemical constituents of the cell wall, along with its low higroscopicity, restricts the movements due to changes in moisture content. Regression analyses to determine the influence of specific gravity and lignin content were performed, concluding that both have a marked importance. Specific gravity shows to be the most important variable, although the influence of lignin is also significant. It is remarked that it is necessary to carry out experimental studies on the effect of these variables on dimensional changes, along with that of other important variables, such as extractives and ray volume.
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