Specific Gravity, Fiber Length, and Extractive Content of Young Paulownia


  • James R. Olson
  • Stanley B. Carpenter


Within-tree variation, wood properties, specific gravity, fiber length, extractive content, growth rate, pulpwood, Paulownia tomentosa


The potential of using paulownia (Paulownia tomentosa) as a pulpwood species was assessed by evaluating the within-tree variation in specific gravity, fiber length, and extractive content of young trees growing on surface-mined land. Stem-wood fiber length and extractive-free specific gravity averaged 0.79 mm and 0.249, respectively. Total average extractive content approached 13%. Compared with other fast-growing hardwoods, paulownia has a lower specific gravity, shorter fiber length, and higher extractive content. All of these factors make paulownia a poor pulpwood species for most types of paper. Its fast growth rate may, however, favor the species as a valuable fiber source for some specialty-type papers where strength is not important.


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