Isatis is a genus of flowering plants in the family Brassicaceae, commonly known as woad. These plants are native to the temperate regions of Europe and Asia. Isatis is best known for its species Isatis tinctoria, which has been historically significant as a source of blue dye. The dye, extracted from the leaves, was widely used in ancient and medieval times before the advent of indigo from tropical regions. The plants typically have yellow flowers and produce elongated seed pods. In addition to its use in dyeing, Isatis has also been studied for its potential medicinal properties, including antiviral and anti-inflammatory effects. The plants thrive in well-drained soils and can often be found in disturbed areas such as roadsides and fields.
