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Abstract
In samples from 20 trees aged 12 to 89 years, rootwood tracheids were one-third longer and one-third larger in diameter and had walls 18 percent thinner and lumens almost two-thirds larger than stemwood tracheids measured at stump height. Tracheids from horizontal roots were longer and had thicker walls than those from roots of other orientations; length, cell diameter, and lumen diameter increased along the root. In vertical roots cell and lumen diameters increased with distance along the root while wall thickness decreased; in oblique roots cell and lumen diameters decreased while length and wall thickness increased. Along the taproot all dimensions increased to a maximum and then decreased.
Citation
Manwiller, Floyd G. 1972. Tracheid dimensions in rootwood of southern pine. Wood Science, Vol. 5(2): 122-124