Depending on the variety, hazelnuts may grow as a bush or small tree which may reach 15 - 20 meters in height. Hazelnuts grow in mild regions of the northern hemisphere. There are five main varieties grown in Turkey: Tombul (fat), the thin-shelled sivri (pointed), badem (almond), kan (blood) and fosa (?). Here they are chiefly grown in the Black Sea region around the cities of Ordu, Samsun and Giresun. Recently hazelnut oil has begun to be used in cooking.