Walnut

The brain-shaped nut from Central Asia

A walnut kernel looks like a brain — and it really is good for the brain! The walnut tree comes from our mountains: the biggest wild walnut forests in the world grow in Fergana and Kyrgyzstan. Alexander the Great took walnuts from here to Greece, which is why Russians call it the 'Greek nut'. One tree lives 300 years and gives 100 kg of nuts a year.

The walnut (Juglans regia) originates in the mountains of Central Asia and Iran; Arslanbob (Kyrgyzstan, at the edge of the Fergana Valley) is the world's largest wild walnut forest at 11,000 ha, and Uzbekistan has natural groves in the Chatkal and Fergana ranges. It grows to 30 m and lives 300–400 years. The kernel is rich in omega-3 fatty acids (the most of any plant), vitamin E and antioxidants — 'brain food'. Its leaves release juglone — other plants won't grow beneath it (allelopathy). Its timber is prized for furniture and gunstocks. China, the USA (California) and Iran are the main producers; Uzbekistan grows and exports more than 20,000 tonnes a year.

Fun facts

• The world's biggest wild walnut forest is at the edge of the Fergana Valley, in Arslanbob.
• Nothing grows under a walnut tree — its leaves release a 'poison'.
• A walnut tree lives 400 years and keeps bearing nuts the whole time.