Wood is a complex and inhomogeneous macromolecular system made up of cellulose, hemicelluloses, lignin, mineral matter, and extractives. Most woods are relatively light in color, but all contain some coloring components. Within these, knowledge of the nature of chromophoric groups is still meager. Casey [1] claimed that almost every pulp component or reaction product is accused of being the carrier of chromophores. While it is generally conceded that the major contributor of color is the lignin component [2], it cannot be precluded that cellulose is not contributing also. In some species the extractives become the controlling factor [3–6]. Color reactions of lignin are a main subject of many textbooks [7–12].