The Eastern Black Oak (quercus velutina) is a common, medium-sized to large oak of the eastern and midwestern United States, with a range that runs essentially east of the Mississippi. Other names for this tree are yellow oak, quercitron, yellow bark oak, or smooth bark oak. It grows best on moist, rich, well-drained soils, but can also grow in less optimal conditions. Its acorns take two years to mature, unlike those of other oaks, and are rather squat and round. It belongs to the family of red oaks.
Black oaks are medium to large trees, growing to a height of 80-100 feet, with trunks about 3 feet in diameter. The leaves have 7-9 lobes, and vary in length, from 4 to 10 inches. During the summer, the leaves are a crisp green color with paler shading underneath. In autumn, the leaves turn to red. The bark of young black oaks is smooth with light grey coloring, but with age, deep furrows develop and the bark becomes thicker and darker. The inner bark is an orangish-yellow color, and it is from this that the dye quercitron is derived.
According to Wikipedia,
Quercitron is a yellow dye obtained from the bark of the Eastern Black Oak (Quercus velutina), a fine forest tree indigenous in North America. The name is a shortened form of quercicitron, from Latin quercus, oak, and citron, lemon, and was invented by Dr. Edward Bancroft (1744-1821), who by act of parliament in 1785 was granted special privileges in regard to the importation and use of the substance. The dyestuff is prepared by grinding the bark in mills after it has been freed from its black epidermal layer, and sifting the product to separate the fibrous matter, the fine yellow powder which remains forming the quercitron of commerce. The ruddy-orange decoction of quercitron contains quercitannic acid, whence its use in tanning, and an active dyeing principle, quercitrin, C21H20O12.
Edward Bancroft was an interesting character, born in the mid-eighteenth century in pre-revolutionary America. During his lifetime he was – according to varying sources – apprenticed to a physician, a scientist, a writer, as well as a spy and double agent during the American Revolutionary War. He was a secretary to American Commission in Paris, working for Benjamin Franklin, as well as spying on the British, and for the British. (Whew! That must have been complicated!) After his life as a spy, his scientific side is credited with having discovered that the inner bark of the Eastern Black Oak, a tree found throughout the midwest and east coast, produced a colorfast and lightfast yellow dye which matched, and possibly surpassed, the common European yellow dyes of the time, such as weld and fustic. Bancroft received English and French patents giving him the right to import the bark, and this made him a rich man in the latter years of his life. Before his death in 1821, Bancroft had published a number of books on natural science, and on dyeing; it is on this latter subject he wrote two volumes, published in 1814: Experimental Researches Concerning the Philosophy of Permanent Colours.
The inner bark of quercus velutina is finely ground before being used as a dye. It is my hope that the harvesting of this bark is done sustainably, without damaging or killing the tree, unless it is harvested for its wood.
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