Isatis tinctoria, with woad or glastum as the common name, is a flowering plant
in the family Brassicaceae. It is commonly called dyer's woad. It is
occasionally known as Asp of Jerusalem. Woad is also the name of a blue dye
produced from the leaves of the plant. Woad is native to the steppe and desert
zones of the Caucasus, Central Asia to eastern Siberia and Western Asia but is
now found in southeastern and Central Europe as well. Long important as a
source of blue dye, it has been cultivated throughout Europe, especially
in Western and southern Europe, since ancient times. In medieval times there
were important woad-growing regions in England, Germany and France. Towns such
as Toulouse became prosperous from the woad trade. Woad was eventually replaced
by the stronger indigo and, in the early 20th century, both woad and indigo were
replaced by synthetic indigos. Used in traditional Chinese medicine for
centuries, woad is now being studied for use in the treatment of cancer. There
has also been some revival of the use of woad for craft purposes.
History of woad cultivation = Ancient use =
The first archaeological finds of woad seeds date to the Neolithic. The seeds
have been found in the French cave of l'Audoste, Bouches-du-Rhône. Impressions
of the seeds of Färberwaid or German indigo, of the plant family, have been
found on pottery in the Iron Age settlement of the Heuneburg, Germany.
The Hallstatt burials of Hochdorf an der Enz and Hohmichele contained textiles
dyed with Färberwaid. Melo and Rondão write that woad was
known "as far back as the time of the ancient Egyptians, who used it to dye
the cloth wrappings applied for the mummies." Skelton informs us that one of
the early dyes discovered by the ancient Egyptians was "blue woad." Lucas writes,
"What has been assumed to have been Indian Indigo on ancient Egyptian
fabrics may have been woad." Hall states that the ancient Egyptians created their
blue dye "by using indigotin, otherwise known as woad."
Julius Caesar reported that the Britanni used to colour their bodies blue with
vitrum, a word that roughly translates to "glass". Many have assumed that
vitrum refers to woad, but other modern authors regard this as a misconception,
possibly repeated for political reasons; Caesar may have been describing some
form of copper- or iron-based pigment. The northern inhabitants of Britain came
to be known as Picts, meaning "painted ones" in Latin, which was due to
accounts of them painting or tattooing their bodies. However, modern
experiments with woad show it does not work as a tattoo pigment, is caustic and
causes scarring when put into the skin. = The medieval period onwards =
Woad was one of the three staples of the European dyeing industry, along with
weld and madder. Chaucer mentions their use by the dyer in his poem The Former
Age: No mader, welde, or wood no litestere.
Ne knew; the flees was of his former hewe
The three colors can be seen together in tapestries such as The Hunt of the
Unicorn, though typically it is the dark blue of the woad that has lasted best.
In Viking age levels at archaeological digs at York, a dye shop with remains of
both woad and madder has been excavated and dated to the 10th century. In
medieval times, centres of woad cultivation lay in Lincolnshire and
Somerset in England, Jülich and the Erfurt area in Thuringia in Germany,
Piedmont and Tuscany in Italy, and Gascogne, Normandy, the Somme Basin,
Brittany and, above all, Languedoc in France. This last region, in the
triangle created by Toulouse, Albi, and Carcassonne, was for a long time the
most productive of woad, or "pastel" as it was known there, one writer
commenting that "woad... hath made that country the happiest and richest in
Europe." The prosperous woad merchants of Toulouse displayed their affluence in
splendid mansions, many of which are still standing. One merchant, Jean de
Bernuy, a Spanish Jew who had fled the inquisition, was credit-worthy enough to
be the main guarantor of the ransomed King Francis I after his capture at the
Battle of Pavia by Charles V of Spain. Much of the woad produced here was used
for the cloth industry in southern France, but it was also exported via
Bayonne, Narbonne and Bordeaux to Flanders, the Low Countries, Italy, and
above all Britain and Spain. A major market for woad was at Görlitz
in Silesia. The citizens of the five Thuringian Färberwaid towns of Erfurt,
Gotha, Tennstedt, Arnstadt and Langensalza had their own charters. In
Erfurt, the woad-traders gave the funds to found the University of Erfurt.
Traditional fabric is still printed with woad in Thuringia, Saxony and Lusatia
today: it is known as Blaudruck"). Medieval uses of the dye were not
limited to textiles. For example, the illustrator of the Lindisfarne Gospels
used a woad-based pigment for blue paint.
Woad and indigo The dye chemical extracted from woad is
indigo, the same dye extracted from "true indigo", Indigofera tinctoria, but
in a lower concentration. Following the European discovery of the seaway to
India, great amounts of indigo were imported from Asia. Laws were passed in
some parts of Europe to protect the woad industry from the competition of the
indigo trade. It was proclaimed that indigo caused yarns to rot: "In 1577 the
German government officially prohibited the use of indigo, denouncing it as that
pernicious, deceitful and corrosive substance, the Devil's dye." "... a
recess of the Diet held in 1577 prohibited the use of 'the
newly-invented, deceitful, eating and corrosive dye called the devil's dye.'"
This prohibition was repeated in 1594 and again in 1603. In France, Henry IV,
in an edict of 1609, forbade under pain of death the use of "the false and
pernicious Indian drug". With the development of a chemical
process to synthesize the pigment, both the woad and natural indigo industries
collapsed in the first years of the 20th century. The last commercial harvest of
woad until recent times occurred in 1932, in Lincolnshire, Britain. Small
amounts of woad are now grown in the UK and France to supply craft dyers. The
classic book about woad is The Woad Plant and its Dye by J. B. Hurry, Oxford
University Press of 1930, which contains an extensive bibliography.
A method for producing indigo dye from woad is described in The History of Woad
and the Medieval Woad Vat ISBN 0-9534133-0-6.
Woad is biodegradable and safe in the environment. In Germany, there have been
attempts to use it to protect wood against decay without applying dangerous
chemicals. Production of woad is increasing in the UK for use in inks,
particularly for inkjet printers, and dyes. The plant can cause problems,
however: Isatis tinctoria is classified as an invasive species in parts of the
United States. Woad and health
Chemicals from woad might be used to prevent cancer, as it can produce high
levels of glucobrassicin. Young leaves when damaged can produce more
glucobrassicin, up to 65 times as much. Indigowoad root is a traditional Chinese
medicine herb that comes from the roots of woad. Literature on traditional
Chinese medicine uses the scientific name Isatis indigotica, although this
name is usually considered synonymous with Isatis tinctoria by botanists. It
is also known as Radix isatidis. The herb is cultivated in various regions of
northern China, namely Hebei, Beijing, Heilongjiang, Henan, Jiangsu, and Gansu.
The roots are harvested during the autumn and dried. The dried root is
processed into granules, which are most commonly consumed dissolved in hot water
or tea. The product is very popular throughout China. Possible minor side
effects include allergic reactions and dizziness; only large dosages or long
term usage can be toxic to the kidneys. Treatments have not generally been
evaluated clinically. Invasive and noxious weed
In certain locations, the plant is classified as a non-native and invasive
weed. It is listed as a noxious weed by the agriculture departments of several
states in the western United States, Arizona, California, Colorado, Idaho,
Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming. In
Montana, it has been the target of an extensive, and largely successful,
eradication attempt. References
24. Renate Kaiser-Alexnat: Wonder Woad. Experiences involving human and plant –
especially woad – reported in pictures and stories“. epubli GmbH, Berlin, 2013.
ISBN 978-3-8442-5590-4 External links
Woad.org.uk - All About Woad - Cultivation, Extraction, Dyeing with
Woad, History and facts about woad The Former Woad Industry Rex Wailes in
Transactions of the Newcomen Society, 1935-36 Vol 16.
The Problem of the Woad - essay debunking the myth of woad as a tattoo
pigment USDA information on Isatis tinctoria
Woad and it's mis-association with Pictish BodyArt