Juglans Juglans Walnut trees are any species of tree in the plant genus Juglans, the type genus of the family Juglandaceae, the seeds of which are referred to as walnuts. All species are deciduous trees, tall, with pinnate leaves , with 5–25 leaflets; the shoots have chambered pith, a character shared with the wingnuts ("Pterocarya"), but not the hickories ("Carya") in the same family. The 21 species in the genus range across the north temperate Old World from southeast Europe east to Japan, and more widely in the New World from southeast Canada west to California and south to Argentina. The
Fruit tree forms whilst keeping the tree short and accessible for harvesting. Other shapes such as cordons, espaliers and fans offer opportunities for growing trees two dimensionally against walls or fences, or they can be trained to function as barriers. Some of the following fruit tree forms require training by tying the branches to the required form. Most require pruning to retain the desired structure. However, not all types of fruit tree are suitable for all forms; apples and pears do well as cordons and espaliers, for example, whereas cherries are more suited to the fan form. An open-centred crown on a short