Macadamia integrifolia Maiden & E. Betche (Proteaceae) Macadamia Nut A small tree with narrow dark green leaves and hanging spikes of white or pinkish flowers, native of N Queensland, growing in dry rainforest but widely cultivated elsewhere in Australia, California, Hawaii and Malawi where it is an important crop. Tree to 6m, bushy when young. Leaves in whorls of 3, 7–15cm long, tapering at the base into a short stalk, often toothed and wavy-edged. Spikes 10–20cm long. Fruit 25–30mm across with a very hard shell, so the edible nut is difficult to extract whole. Macadamia tetraphylla L. Johnson from Queensland and NSW, has stiffer, sharply toothed leaves with a rounded base; it is also edible.