Spruce, Sitka

Hemlock-Sitka spruce 2 -100 25% from Sitka spruce... 

Fig. 2. Sitka spruce sensitivity to wind (after Petty Swain, 1985).

The value of spruce-oil chemistry in sorting out problems of hybridization and introgression—major factors in Picea taxonomy—was succinctly summarized by von Rudloff who defined three situations (1) Terpene variation is limited such that it is not possible to use these characters in studies of introgression this is the case in eastern North America where the ranges of black spruce and red spruce overlap. (2) Sufficient variation in terpene profiles exists for the compounds to be useful markers in systematic studies as seen in white spruce. Brewer s spruce, and Sitka spruce. (3) Tree-to-tree variation in terpene content is so variable that use in che-mosystematic studies is precluded, or at least requires very large sample sizes for statistical reliability, as seen with Engelmann s spruce. 

J. Grayston and C. D. Campbell, Functional biodiversity of microbial communities in the rhizospheres of hybrid larch (Larix eurolepis) and Sitka spruce (Picea sitch-ensi.s). Tree Physiol. 76 1031 (1996). 

A comprehensive study of the properties of acetylated wood was undertaken by the Forest Products Laboratory in Madison, Wisconsin, and included an investigation of the mechanical properties of acetylated wood (Tarkow etal., 1946). The property changes were not significant, but there was some variation between species. For example, Sitka spruce and basswood exhibited increases in strength and MOE upon acetylation to about 20 % WPG, whereas yellow birch showed a decrease in these properties at 16 % WPG. 

Fuwape, J.A. and Oyagade, A.O. (1999). Strength and dimensional stability of acetylated Gmelina and Sitka spruce particle board. Journal of the Timber Development Association of India, 45(1/2), 5-10. 

Kubojima, Y., Okano, T. and Ohta, M. (1998). Vibrational properties of Sitka spruce heat-treated in nitrogen gas. Journal of Wood Science, 44(1), 13-11. 

Yano, H., Norimoto, M. and Yamada, T. (1986a). Changes in acoustical properties of Sitka spruce due to acetylation. Mokuzai Gakkaishi, 32(12), 990-995. 

Street, R. A., S. C. Duckham, and C. N. Hewitt, Laboratory and Field Studies of Biogenic Volatile Organic Compound Emissions from Sitka Spruce (Picea sitchensis Bong.) in the United Kingdom, J. Geophys. Res., 101, 22799-22806 (1996). 

Nielson, K. E., U. L. Ladekarl, and P. Nornberg. 1999. Dynamic soil processes on heathland due to changes in vegetation to oak and sitka spruce. Forest Ecology and Management 114 107-116. 

European birch,76 maple,77 Scots pine,78 maritime pine,79 slash pine,80 southern pine,81 black spruce,78 Sitka spruce,82 and white spruce83 contain the same main structural features. 

The important thing to remember in most of these experiments is that the bacteria have been used to improve the permeability of sapwood. For species like Sitka spruce which has sapwood that is impermeable to creosote, this type of treatment may prove to be commercially feasible. However, in order to fully exploit this method for increasing permeability, it will be necessary to find bacteria which have the ability to degrade heartwood pit membranes. Indeed, this may be possible since Greaves (50) has shown that some bacteria can increase the permeability of heartwood. In addition to this, it would be desirable to accelerate the reaction as much as possible in order to make it compatible with a commercial operation. 

C. Heat Treatments. Several woods have been heated under wet and dry heating conditions to determine the effect heat has on the decay resistance of these woods. Alaska-cedar, Atlantic white-cedar, bald cypress, Douglas-fir, mahogany, redwood, white oak, Sitka spruce, and western redcedar were heated under dry conditions or wet conditions at temperatures of 80-180°C for varying lengths of time. Boyce (11) found that dry heat at 100°C or steam heat at 120°C for 20 minutes had no effect on the decay resistance. Similar results were observed by Scheffer and Eslyn (12) in soil-block tests with Lenzites trabea for the heated softwoods and Polyporus versicolor for the heated hardwoods. 

Figure 1. Logarithm of heating time vs. temperature required to give three different reductions in swelling and shrinking when the heating was done beneath the surface of a molten metal to exclude oxygen (15). 0,1/16-in. thick Sitka spruce veneer , 1/2-in. thick cross sections of western white pine O, 3/8-in. flat sawn western white pine O, 15/16-in. thick eastern pine boards. Numbers on plot indicate antishrink efficiency (A.S.E.) in percent.

Figure 2. External volumetric shrinkage vs. relative vapor pressure for thin Sitka spruce cross sections containing originally different quarter-saturated salt solutions (29)...

Burton KW, Morgan E, Roig A. 1986. Interactive effects of cadmium, copper and nickel on the growth of Sitka Spruce and studies of metal uptake from nutrient solutions. New Phytol 103 549-557. 

Yano et al. [53] studied acoustic properties of acetylated Sitka spruce by specific dynamic Young s modulus and by logarithmic decrement. For oven-dried specimens, both the modulus and the decrement have been found to increase. Meanwhile, mechanical properties are generally unchanged and adhesive strength is reduced by acetylation [2]. Furthermore, creep deformation of wood under humidity change is remarkably reduced by acetylation [54]. 

Specimens of Sitka spruce Picea sitchensis) and Glehn spruce Picea glehnii) were modified by eight kinds of chemical treatment. Weight percent gain (WPG) resulting from each chemical treatment was determined based on the over-dry weight of the specimen before and after treatment. 

McKay, S.A., Hunter, W.L., Godard, K.A., Wang, S.X., Martin, D.M., Bohlmann, J. and Plant, A.L. (2003) Insect attack and wounding induce traumatic resin duct development and gene expression of (—)-pinene synthase in Sitka spruce. Plant Physiol, 133, 368-78. 

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