Isatis tinctoria
A flowering plant historically used as a blue dye and medicine.
Isatis tinctoria, known as woad, dyer's woad, dyer's-weed, or glastum, is a flowering plant from the mustard family. Its history includes use as both a blue dye and a medicinal herb. The name *Isatis* points to its ancient role in treating wounds, while *tinctoria* refers to dyeing. It is sometimes called Asp of Jerusalem. The term "woad" also describes the blue dye made from the plant's leaves. Originally native to steppe and desert areas from the Caucasus and Central Asia through Eastern Siberia and Western Asia, it now also grows in parts of South-Eastern and Central Europe and western North America.
Woad was a major source of blue dye, cultivated across Europe, especially in the west and south. During medieval times, key growing regions included England, Germany, and France. Towns like Toulouse grew wealthy from the woad trade. Cultivation spread throughout Europe, making woad an important trade item. Starting in the 16th century, indigo (*Indigofera tinctoria*), from Subsaharan Africa and South and Southeast Asia, began to replace it. By the early 20th century, both woad and indigo had largely been replaced by synthetic blue dyes, though woad has seen some revival for craft use.
The earliest archaeological evidence of woad seeds dates to the Neolithic period, found in a cave in Bouches-du-Rhône, France. Impressions of woad seeds appear on Iron Age pottery from Heuneburg, Germany, and seed and pod fragments were found in an Iron Age pit at Dragonby, North Lincolnshire, UK. Textiles dyed with woad were discovered in the Hallstatt burials of the Hochdorf Chieftain's Grave and Hohmichele. It is very likely woad was used as a dye in ancient Egypt.
A passage from Julius Caesar's *Commentaries on the Gallic War* describes Britons painting themselves with *vitrum*, which produces a dark blue color, making them look more frightening in battle. *Vitrum* is often translated as "woad," but more commonly means "glass." Experimental body paints made from woad with different binders produced colors ranging from grey-blue to intense midnight blue to black. While some have argued woad was used for tattooing, experiments have failed due to its caustic nature. Analysis of the Lindow Man bog body from the late Iron Age or early Roman period suggests Britons may have used a copper- or iron-based pigment for body decoration.
During the medieval period, woad was a key dye
- type
- Flowering plant
- family
- Brassicaceae (mustard family)
- native_range
- Caucasus, Central Asia to Eastern Siberia, Western Asia
- introduced_range
- South-Eastern and Central Europe, western North America
- primary_use
- Blue dye and medicinal plant
- dye_chemical
- Indigo (same as Indigofera tinctoria but lower concentration)
- also_known_as
- Woad, dyer's woad, dyer's-weed, glastum, Asp of Jerusalem
Quick Facts
- Genus
- Isatis
- Species
- tinctoria
Facts from the source article.
Lore & Background
The first archaeological finds of woad seeds date to the Neolithic period, with seeds found in a cave in Bouches-du-Rhône, France, and impressions on pottery from the Iron Age settlement of Heuneburg, Germany. Textiles dyed with woad were found in the Hallstatt burials of the Hochdorf Chieftain's Grave and Hohmichele. It is highly likely woad was used as a dye in ancient Egypt. A passage in Julius Caesar's Commentarii de Bello Gallico describes Britons painting themselves with vitrum, which has frequently been translated as 'woad' but more typically means 'glass'; experimental body paint from woad has yielded colors from grey-blue to black, though its caustic nature has made tattooing experiments unsuccessful.
Reader's Guide
Woad was an important source of blue dye and was cultivated throughout Europe, especially in Western and Southern Europe. In medieval times, important woad-growing regions existed in England, Germany, and France, with towns like Toulouse prospering from the trade. Woad was one of the three staples of the European dyeing industry, along with weld (yellow) and madder (red). From the 16th century, indigo from Indigofera tinctoria started to replace it, and by the early 20th century, both were mostly replaced by synthetic blue dyes. Laws were passed in some parts of Europe to protect the woad industry from indigo competition, including a French edict punishing the use of indigo by death. The last commercial harvest of woad until recent times occurred in 1932 in Lincolnshire, Britain. Today, small amounts are grown in the UK and France for craft dyers, and production is increasing in the UK for use in inks and dyes. In certain western US states, it is classified as a non-native and invasive noxious weed.
Did You Know?
- The dye chemical extracted from woad is indigo, the same dye as from 'true indigo' (Indigofera tinctoria), but in a lower concentration.
- In France, Henry IV issued an edict in 1609 punishing by death the use of 'the false and pernicious Indian drug' (indigo).
- The last commercial harvest of woad until recent times occurred in 1932 in Lincolnshire, Britain.
- Woad is listed as a noxious weed by the agriculture departments of eleven western US states, including Arizona, California, and Oregon.
Frequently Asked Questions
What is Isatis tinctoria?
It is a flowering plant in the mustard family (Brassicaceae) most commonly called woad or dyer's woad. Throughout history it has been prized for two main purposes: producing a blue dye from its leaves and serving as a traditional medicinal herb.
What dye does Isatis tinctoria produce?
Its leaves yield indigo, the same blue pigment compound found in Indigofera tinctoria, though woad carries a lower concentration of it. The word "woad" itself can refer either to the living plant or to the blue pigment extracted from its foliage.
What medicinal uses is Isatis tinctoria known for?
The genus name "Isatis" reflects its long-standing role in treating wounds, and the plant has been employed as a medicinal herb alongside its dyeing function. In folk tradition it is sometimes called "Asp of Jerusalem," a name that hints at its older healing reputation.
Where does Isatis tinctoria originally grow?
It is native to steppe and desert regions stretching from the Caucasus and Central Asia through Eastern Siberia and Western Asia. It has since been introduced to parts of South-Eastern and Central Europe as well as western North America.
What do the two parts of the name Isatis tinctoria actually mean?
The genus name "Isatis" points to the plant's ancient wound-treating role, while the specific epithet "tinctoria" directly references its dyeing purpose. Together the binomial essentially encodes both of its primary historical uses in a single name.
More in Herbs & Spices & Medicinal 1-19
Spotted an error? Know more?
This is a living reference — every entry is fact-audited, and reader corrections feed straight into our audit queue. Suggest an edit · See this site's audit record