Of woody tissue

William Spackman Only about 20% of the cells of woody tissue contain protoplasm and hence proteinaceous material. It is true therefore that woody tissue is a poor source of nitrogen. 

Codification of Woody Tissue as Deduced From a Petrographic Study of Brandon Lignite... 

Fig. 4.6.10. Polarized Raman spectra from approximately 1 n domain of the secondary wall in a longitudinal section of woody tissue a electric vector parallel to the cell wall b electric vector perpendicular to the wall...

There is evidence to suggest that the late Paleozoic was a time of very elevated po, to concentrations substantially greater than observed in the modern atmosphere. Coals from the Carboniferous and Permian contain a greater abundance of fusain, a product of woody tissue combustion and charring, than observed for any period of the subsequent geologic past (Robinson, 1989, 1991 Glasspool, 2000), suggesting more abundant forest fires and by implication possibly... 

As industry is more concerned with the amount of woody tissue in a given volume of timber an alternative definition of density, the nominal density, is often preferred ... 

Relatively weak absorptions at wavelengths above 400 mn are snfficient to cause the perception of color. The color of woody tissue varies widely from off-white (e.g., aspen, birch), yellow (e.g., spruce, pine, fir), amber-orange (e.g., western hemlock, Douglas fir, red cedar, teak) and rich browns (walnnt). While some of this color is dne to tannins and other extractives, in most species the color originates from chromophores in the lignin. 

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