Observation of eucalyptus trees in suburbia

By Bruce Naylor

After reading an article in Hort Journal relating to the use of Eucalyptus species in landscape design in suburbia, I feel prompted to bring up the subject of using Eucalyptus in suburban gardens to your attention. For some perspective, I have been involved in the industry in Queensland for over 50 years, most of it as a grower and I am a Life Member of the Nursery & Garden Industry Queensland (NGIQ). I am also from ‘the country’ and respect the order of the natural landscape.

I have noticed over the years several Eucalyptus species blown over in suburban situations. On closer examination, you will notice that the root system is poor or limited in its development. All that remains in these cases is a tight circle of roots close to the trunk. Notwithstanding the separate matter of adequate root development from the seedling stage (an issue for another day), the issue of concern is our constant irrigation of species like this that does not match their natural requirements. In the country, if a Eucalyptus tree is pulled down via scrub clearing, roots fly up out of the ground a considerable distance from the main trunk.

It makes me conclude that Eucalyptus in suburbia should not be subjected to the constant watering we submit them to, as it kills off most of their root system, and if they are used, should be planted outside the irrigation zone where they can rely only on rainfall and let their root systems develop accordingly.