When I enlarge the images I can see that most of the trees have wrinkly armpits where the branch joins the trunk (usually indicative of scribbly gum in our region). Some of the trees may also be brittle gum which usually don't have wrinkly armpits and when you run your thumb along the trunk will leave a chalk like residue (which scribbly gum usually doesn't)
Thanks Michael. I'll get some close up photos of the wrinkly armpits. Sorry, I just didn't think about showing that in the photos. I'm pretty sure we don't have any brittle gums but I'll keep my eye out.