While working out in the Foxes lair gym (Claypit walk), I noticed misshapen wandoos with several stems arising from stumps that had been logged decades ago to make fence posts and sheep yards.
Trees are actually a layer of living tissue around a dead (wood) core. Eucalypts are amazingly tough, having evolved to survive in our infertile soils. When the heartwood in a living tree rots or is eaten by termites, nutrients tied up in the wood are released for the tree to use. Resulting holes provide hiding places and nest sites for the wildlife. Below are a few examples, but there are many more.