Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575–585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In the RGB color model, used to create colors on television and computer screens, yellow is a secondary color made by combining red and green at equal intensity. Carotenoids give the characteristic yellow color to autumn leaves, corn, canaries, daffodils, and lemons, as well as egg yolks, buttercups, and bananas. They absorb light energy and protect plants from photo damage in some cases. Sunlight has a slight yellowish hue when the Sun is near the horizon, due to atmospheric scattering of shorter wavelengths.
Flavonoids are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans.
Maclura tinctoria, known as old fustic and dyer's mulberry, is a medium to large tree of the Neotropics, from Mexico to Argentina. It produces a yellow dye called fustic primarily known for coloring khaki fabric for U.S. military apparel during World War I. This dye contains the flavonoid morin. It is dioecious, so both male and female plants are needed to set seed.
Quercitron is a yellow natural dye obtained from the bark of the Eastern Black Oak, a forest tree indigenous in North America. It was formerly called Dutch pink, English pink, or Italian pink.
Cotinus coggygria, syn. Rhus cotinus, the European smoketree, Eurasian smoketree, smoke tree, smoke bush, Venetian sumach, or dyer's sumach, is a Eurasian species of flowering plant in the family Anacardiaceae.
Vat dyes are a class of dyes that are classified as such because of the method by which they are applied. Vat dyeing is a process that refers to dyeing that takes place in a bucket or vat. The original vat dye is indigo, once obtained only from plants but now often produced synthetically.
Kaempferol (3,4′,5,7-tetrahydroxyflavone) is a natural flavonol, a type of flavonoid, found in a variety of plants and plant-derived foods including kale, beans, tea, spinach, and broccoli. Kaempferol is a yellow crystalline solid with a melting point of 276–278 °C (529–532 °F). It is slightly soluble in water and highly soluble in hot ethanol, ethers, and DMSO. Kaempferol is named for 17th-century German naturalist Engelbert Kaempfer.
Calendula officinalis, the pot marigold, common marigold, ruddles, Mary's gold or Scotch marigold, is a flowering plant in the daisy family, Asteraceae. It is probably native to southern Europe, but its long history of cultivation makes its precise origin unknown, and it is widely naturalised.
Flavonols are a class of flavonoids that have the 3-hydroxyflavone backbone. Their diversity stems from the different positions of the phenolic –OH groups. They are distinct from flavanols such as catechin, another class of flavonoids, and an unrelated group of metabolically important molecules, the flavins, derived from the yellow B vitamin riboflavin.
A dyewood is any of a number of varieties of wood which provide dyes for textiles and other purposes. Among the more important are:
Genista tinctoria, the dyer's greenweed or dyer's broom, is a species of flowering plant in the family Fabaceae. Its other common names include dyer's whin, waxen woad and waxen wood. The Latin specific epithet tinctoria means "used as a dye".
Puccoon is a common name that refers to any of several plants formerly used by certain Native Americans for dyes. The dyes were made from the plants' roots.
Anthoxanthins are a type of flavonoid pigments in plants. Anthoxanthins are water-soluble pigments which range in color from white or colorless to a creamy to yellow, often on petals of flowers. These pigments are generally whiter in an acid medium and yellowed in an alkaline medium. They are very susceptible to color changes with minerals and metal ions, similar to anthocyanins.
Alkanet is the common name of several related plants in the borage family (Boraginaceae):
Fisetin (7,3′,4′-flavon-3-ol) is a plant flavonol from the flavonoid group of polyphenols. It can be found in many plants, where it serves as a yellow/ochre colouring agent. It is also found in many fruits and vegetables, such as strawberries, apples, persimmons, onions and cucumbers. Its chemical formula was first described by Austrian chemist Josef Herzig in 1891.
Reseda luteola is a flowering plant species in the family Resedaceae. Common names include dyer's rocket, dyer's weed, weld, woold, and yellow weed.
Rubia tinctorum, the rose madder or common madder or dyer's madder, is a herbaceous perennial plant species belonging to the bedstraw and coffee family Rubiaceae.
Natural dyes are dyes or colorants derived from plants, invertebrates, or minerals. The majority of natural dyes are vegetable dyes from plant sources—roots, berries, bark, leaves, and wood—and other biological sources such as fungi.
Dyeing is the craft of imparting colors to textiles in loose fiber, yarn, cloth or garment form by treatment with a dye. Archaeologists have found evidence of textile dyeing with natural dyes dating back to the Neolithic period. In China, dyeing with plants, barks and insects has been traced back more than 5,000 years. Natural insect dyes such as Tyrian purple and kermes and plant-based dyes such as woad, indigo and madder were important elements of the economies of Asia and Europe until the discovery of man-made synthetic dyes in the mid-19th century. Synthetic dyes quickly superseded natural dyes for the large-scale commercial textile production enabled by the Industrial Revolution, but natural dyes remained in use by traditional cultures around the world.
