Barley ears. Ears of barley (Hordeum sp.). Barley is a very popular world crop. It is used in the brewing industry as the staple crop for beer production, and is used widely in cookery for its nutritional value. Barley is a good source of vitamin E, most B-complex vitamins, and the minerals potassium, calcium, and iron. It is thought to be the earliest cultivated crop: it was grown by the Egyptians around 5,000 years ago.