Douglas-fir wood quality studies Part II: Effects of age and stimulated growth on fibril angle and chemical constituents
✍ Scribed by Harvey D. Erickson; Tsuneo Arima
- Publisher
- Springer
- Year
- 1974
- Tongue
- English
- Weight
- 602 KB
- Volume
- 8
- Category
- Article
- ISSN
- 0043-7719
No coin nor oath required. For personal study only.
✦ Synopsis
The same material was used as in Part I of this study. Fibril angle decreased with age from over 30 degrees to 7 degrees at about age 30. Accelerated growth by fertilization and thinning at about 20 years caused a slight increase in angle but only for a few years. The semilog correlation with age was very high, r = 0.96. Tracheid length was highly correlated with fibril angle, r = 0.94. Growth rate and percent latewood were minor causes of changes in fibril angle. Extractive content did not change significantly with plot treatment. Lignin percent was highest near the pith and decreased to about age 20; r was 0.94 for the controls using the log of age. Accelerated growth increased lignin compared to the control trees by about 0.7%. Holocellulose and alpha cellulose increased from the pith to about 20 years of age. Accelerated growth caused a small decrease of 0.9% for both constituents during the next 6 years compared to uniform-growth trees, then the differences became much less.