Dyer's-broom, also known as the botanical name Genista tinctoria, is a plant that has been used for centuries as a natural dye. The plant is known for its bright yellow flowers and can grow up to four feet tall. There are many synonyms for dyer's-broom, including "dyer's greenwood," "waxen woad," "dyeweed," and "green weed." These plant names reflect the plant's usefulness in dyeing wool and other textiles. Dyer's-broom has also been used in herbal medicine as a diuretic and a treatment for skin inflammation. Whether using it to create vibrant dyes or for medicinal purposes, dyer's-broom has been an important plant for centuries.