Australian Native Macadamia
Macadamia integrifolia
 
A small  medium sized tree, growing to 15 metres in height. Native to rainforests in south east Queensland and northern New South Wales, Australia. Common names include Macadamia, Smooth-shelled Macadamia, Bush Nut, Queensland Nut and Nut oak.
 
Seedling (nb: images are mature fruit trees).