الفهرس 
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Abstract
The hypothesis is examined that short-term creep response of earlywood and latewood tissues of some coniferous species, stressed in tension parallel to the grain, is a function of microfibril angle of the S2 layer of and relative degree of crystallinity in the tracheid cell wall, along with specific gravity of that wood tissue and its extractives content.
A new technique was developed to measure the total creep that occurred over a 60-minute period of time for small specimens (nominally 0.010 in,thick) of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) (normal and compression wood),Sitka spruce (Picea sitchensis (Bong.) Carr.) and western hemlock (Tsuga heterophylla (Raf.) Sarg.), taken from earlywood and latewood zones of the same increment. Total creep was determined at two initial deformation levels, 3,000 microin.per in. (strain level No. 1) and 6,000 microin. per in. (strain level No. 2).Microfibril angle was measured by a modified mercury impregnation method, while cell wall crystallinity was determined on small, unoriented pellets by the X-ray diffraction technique. Air-dry specific gravity (oven-dry weight) and alcohol-benzene plus hot water extractives