Pastel (Isatis praecox)

Annual glaucous cruciferous plant, with oblong petiolate inner leaves, sessile sagittate upper leaves; small yellow flowers, gathered in corymb; pendulous silicles, indistinctly winged. From the leaves of this plant, a blue dye principle is extracted, capable of replacing indigo and which was widely used in the past by Madeiran dyers. Madeira used to export some pastel to Portugal, as seen from some notes that João Gonçalves Zargo received from Infante D. Henrique, in which he said: 'be reminded to send the pastel that is corrected, and tell João Affonso to send some if it is corrected.' Correcting the pastel was probably simply drying it in the sun, or then crushing its leaves, letting the obtained mass lose water and reducing the same mass to balls, after having let it undergo a beginning of fermentation for 8 to 12 days. Pastel is not only useful for dyeing; it is also a valuable forage for cattle and sheep. In Camara de Lôbos, its juice is used in the treatment of pimples and other skin conditions.