The sap has a number of medicinal uses including use as an antiseptic and remedy for stomach upsets. (Personally I think that's because it tastes so bitter that any child offered it quickly says "No thanks, I'm fine now Mum!"). At this time of year you often see the trees 'bleeding'. The Cockatoos come, listen for grubs under the tree bark and tear them out, leaving a 'wound' if you like. See photo.
In any case it's a beautiful tree and the one people know for it's 'Honkey Nuts'. These nuts are an important food source for a variety of our native birds, who eat the seeds found inside. If you look at the photo of the nuts you can see evidence of two sorts of birds. The nut which is damaged with a large chunk out of it has probably been fed on by a Port lincoln Ringneck Parrot (also known as a 'Twenty Eight'). White Tailed Black Cockatoos also eat them. If you look really closely at the other one, on the right, you can see tiny little 'C' shaped markings on it. This nut's seeds were taken by a Red-capped parrot. These beautiful birds have evolved with a longer top beak. They hold the nut with one foot, insert the lower part of their beak into the nut (that makes the mark) and use the top part as a lever to prise/slide the seeds out without damaging the nut.You can tell a lot about what lives in an area from looking at the food sources. Sadly a lot of people in the Hills take down these trees because the Honkey nuts are annoying (might drop on your car, or make a mess in the driveway). We need to share with people the importance of these trees as a food source for our declining bird populations and hopefully inspire more people to keep them and plant more. Perhaps if this post was new info to you, you'll do just that.