Google map of Barangaroo & other iconic sites nearby.

Google map of Barangaroo & other iconic sites nearby.

Barangaroo is an iconic harbourside area in the City of Sydney that is being redeveloped. It is of important historical significance. The western promenade more so, because what is put there will showcase what the NSW government wants to show the world. One would therefore think representing the area’s heritage & character to the millions of local & foreign visitors is a top priority.

I was horrified to read an article in the Sun-Herald that an avenue of more than 100 American Honey locust trees (Gledistia triacanthos) are being planned for this iconic site.  See –   It says that local landscape architects have written to the NSW Premier Baird to intervene to stop the planting.

Native to North America, the Honey locust is a rapid growing deciduous tree that grows to 20-metres. In October to November it blooms with creamy-yellow hanging flower stalks that develop into 20-30 cm long brown seedpods. It produces prolific seeds.

The tree is covered with large 3-10 cm thorns. There are so-called ‘thornless’ varieties, but these tend to produce thorns eventually. Their large thorny branches have a tendency to drop in windstorms.

They spread through the droppings of animals, carried in water flows or by suckering. There is a real risk that their seeds will be carried all around Sydney Harbour.

The species is a major invasive weed in many Australian areas.  The State of Queensland started an eradication program in 1993.   Honey locust trees cannot be sold anywhere in Queensland & all trees discovered must be destroyed.  They are also a problem on the NSW North Coast.

The Australian government’s Environment Department describes the species as an aggressive exotic tree. It says, “Although beneficial in the short term as stock feed, the long term consequences of its growth & spread are counter productive.  Honey locust is an invasive tree capable of out-competing & replacing native vegetation.”

They are described as being able to spread at an uncontrollable rate. Bulldozing them only serves to help them spread as they vigorously regrow from their broken trunks. Poisoning with herbicides is the recommended method of killing them.

They are not an appropriate tree for this harbourside location.

The NSW government department (Barangaroo Delivery Authority) seems to have uncritically accepted the choice without any thinking of its own. For such an iconic area of Sydney, I would have thought Australian native trees could have been planted. Instead we will get thorny exotic trees declared a noxious weed in some parts of Australia.

I would have expected the government department responsible for delivering such an important piece of public infrastructure to have been a good deal more astute when it received this recommendation from a foreign-based consultant, as opposed to slavishly accepting it. I hope the NSW Premier listens to the desperate calls from the local experts & stops the planting.

Thorns of a Honey locust tree - decalred as a Class 1 Pest Plant in Queensland.  Photo by Department of Agriculture, Fisheries & Forestry Biosecurity Queensland - used with thanks.

Thorns of a Honey locust tree – declared as a Class 1 Pest Plant in Queensland.   I can’t imagine they will plant these, but even non-thorny varietties eventually do grow thorns.  Photo by Department of Agriculture, Fisheries & Forestry Biosecurity Queensland – used with thanks.