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 tree pollination deliberately as part of a selective breeding program for fruit trees with desired attributes. Trees that are cross-pollinated or pollinated via an insect pollinator produce more fruit than trees with flowers that just self-pollinate. In fruit trees, bees are an essential part of the pollination process for the formation of fruit. Pollination of fruit trees around the world has been highly studied for hundreds of years. There is a lot of information known about fruit tree pollination from temperate climates, but very little information known about fruit tree pollination from tropical climates. Fruits from temperate climates include apples, pears, plums,