These beautiful trees with their distinctive butterfly-shaped leaves and strange seeds are, for many, the essence of South Africa areas, along with interesting bird and insect life and game animals. They are also an extremely important food source for animals and people. Vast tracts of uninterrupted mopane scrub and woodland characterize the hot, low-lying areas near the Limpopo River in the far north of South Africa. The compound leaves are divided in two so that the leaflets resemble butterfly wings. Crushed leaves have a turpentine odour. In summer the leaves are fed on by swarms of fat, dark greyish mopane worms, which can reach almost 10 cm long. These are rich in protein and are eaten by people, either roasted or dried. The sale of dried mopane worms is an important income source for many people, creating a local economy. Other traditional uses of the mopane tree include the making of houses and kraal fences, twigs chewed as tooth brushes, the bark is used to make twine and for tanning, and the leaves used for healing wounds. The hard, reddish heartwood timber was used to make railway sleepers and as props for mining activities.