Sorry Pam call me stupid but "What is a Nullabor Nut" do you have a pic,
does it come from a tree or maybe a shrub, is it a native I looked up all my books
and cannot find any reference to it anywhere even under common names......MM.

MM, I don't have a pic, sorry, don't have anything - it's just a tree. I remember seeing mention of it somewhere a few weeks ago, then saw it at the nursery during the week.