What is a straw plaiting used for bonnets and hats, made from the straw of a particular kind of wheat, grown for the purpose in Tuscany, Italy; -- so called from Leghorn, the place of exportation called?

leghorn — A straw plaiting used for bonnets and hats, made from the straw of a particular kind of wheat, grown for the purpose in Tuscany, Italy; -- so called from Leghorn, the place of exportation. (Webster's 1913.)

Sources