Walnut

Introduced by the Romans, the walnut has long been valued for its tasty nuts. It is also a handsome specimen tree for the larger garden, forming a short trunk and broad crown, clothed in shiny, bright green, pinnate leaves composed of oval leaflets. The leaves are distinctly aromatic when crushed. In autumn, the foliage turns shades of yellow and bronze. The smooth bark is olive-brown when young, maturing to silvery-grey. Drooping male catkins appear in spring whilst pollinated female flowers turn into green leathery husks that contain nutritious walnuts on older trees. Walnuts provide food for numerous insects, and the nuts are highly attractive to small mammals. Although partially self-fertile, cross-pollination ensures the best crops. Height: 30m (100ft). 15m (50ft).