Juglans regia Juglans regia Juglans regia, the Persian walnut, English walnut, Circassian walnut, or especially in Great Britain, common walnut, is an Old World walnut tree species native to the region stretching from the Balkans eastward to the Himalayas and southwest China. The largest forests are in Kyrgyzstan, where trees occur in extensive, nearly pure, walnut forests at 1,000–2,000 m (3000 to 7000 ft) altitude—notably at Arslanbob in Jalal-Abad Province. It is widely cultivated across Europe. "Juglans regia" is a large, deciduous tree attaining heights of 25–35 m (80 to 120 ft), and a trunk up to 2 m (6 ft) diameter,
Fruit contrast, rhubarb is often referred to as a fruit, because it is used to make sweet desserts such as pies, though only the petiole (leaf stalk) of the rhubarb plant is edible, and edible gymnosperm seeds are often given fruit names, e.g., ginkgo nuts and pine nuts. Botanically, a cereal grain, such as corn, rice, or wheat, is also a kind of fruit, termed a caryopsis. However, the fruit wall is very thin and is fused to the seed coat, so almost all of the edible grain is actually a seed. The outer, often edible layer, is the "pericarp", formed