Of plants used for dyeing, the principal are bastard saffron, madder, woad and the indigo plant.
Attempts to trace the architecture of Central America directly from Old-Woad types have not been successful, while on the other hand its decoration shows proof of original invention, especially in the imitations of woodwork which passed into sculptured ornament when the material became stone instead of wood.
Of dye-stuffs there are produced henna (Lawsonia iijermis) principally grown at Khabis near Kermn, woad and madder; a small quantity of indigo is grown near Dizfu and Shushter.
The only industrial plants were flax and the dye-plants, chief among which were woad and rud, roid (a kind of bed-straw?).
Among the vegetable products not yet mentioned the most important are the mulberry, grown in almost all provinces, but principally in those bordering on the Mediterranean, and above all in Valencia, the chief seat of the Spanish silk production and manufacture; tobacco, which is also imported, hemp and flax, grown chiefly in Galicia and other northern provinces; among dye-plants, madder, saffron, woad (Isatis tinctoria), and wild woad or dyers weed (Reseda luteola); ground-nuts (Arachis hypogaea), grown for their oil, for the preparation of which the nuts are exported in considerable quantity to France; liquorice, cummin, colocynth, &c. Esparto, chiefly from the arid lands of the south-east, is largely exported to Great Britain.