answer:Was this a serious question? On the off-chance that it was, here goes. The macadamia tree is native to Australia. It its native environment, it is subject to attack by more than 150 types of pest (That’s Australia for you, an environment not for the faint of heart.) including the macadamia nut borer (thus the hard shell). Darn you, spendywatson, now I am having a craving for macadamia nuts!