One year on from Cyclone Marcus, a Darwin tree-planting scheme promises not to repeat past mistakes

By Kate Ashton

Posted March 16, 2019 10:08:03

In 1974 when Cyclone Tracy devastated Darwin, the community began the gruelling process of putting the city back together again.

Key points:

  • Hundreds of African mahoganies planted after Cyclone Tracy were uprooted during Cyclone Marcus, causing serious damage
  • The Darwin Council has a new tree-planting program that favours hardier native species
  • African mahoganies are now on a “not to be planted” list

The Darwin Council and the Northern Territory government handed out free African mahogany saplings, a tree that was attractive to Top Enders because it was fast-growing, easy to maintain, and would mature to provide plenty of shade.

But that decision would prove costly in the decades to follow, as the shallow-rooted trees turned out to be a serious public hazard, their unpredictable tendency to drop enormous branches at random causing the deaths of at least two people.

The NT coroner found that deaths of nine-year-old boy Aiden Bott, who died after a branch fell on him at a Darwin primary school in 2008, and 62-year-old William Brown, who was killed by a falling branch at a Darwin golf club, were both preventable.

Last year during Cyclone Marcus, the economic cost of the decision to plant African mahoganies across the Top End was on full show, as hundreds of massive trees facing their first major storm since Tracy were uprooted during wind gusts of more than 130km/h, blocking roads and seriously damaging cars and homes.

Cyclone Marcus made landfall a year ago in Darwin on the morning of March 17, and Darwin City Council has since embarked on a new tree-planting program, saying it has learned from the lessons of the past.

‘The right tree for the right spot’

Darwin Council has conducted extensive research into the tree types most likely to be able to survive a cyclone, and produced a list of 25 trees on a “not to be planted” list, including African mahoganies.

“The Darwin Council actually hasn’t planted an African mahogany for about the last 15 years, we learnt that lesson some time ago,” said Jamie Lewis, a technical officer for the Parks and Reserves Department at the council.

“The important thing is we learn from planting those unsuitable trees and don’t do it again.”

There is a long list of mainly native species that the council will focus on planting this time around, including the Canarium australanium, but there’s no hard and fast rule about which trees are the most likely to survive cyclones.

“It’s about trying to find the right tree for the right spot,” Mr Lewis said.

“Different trees have different attributes: trees that are suitable for providing shade, pretty trees to provide colour, native trees to provide good habitat and food sources for wildlife.”

The council is also offering a service for residents to call up and ask what trees might be best for them, and also request new trees be planted on verges near their homes.

“It’s going to take us ten-plus years to get some of that canopy cover back that we lost, but it’s important we start now, so we’re taking the first steps in that process of recovery now,” Mr Lewis said.

The City of Darwin is aiming to plant 5,000 new trees by the end of the year.

‘Not a single leaf on the trees remained’

With the benefit of hindsight, it is easy to say that planting short-lived species like the African mahogany was a bad idea.

It is important to remember just how bad the damage from Cyclone Tracy was, said Associate Professor of Emergency and Disaster Management at Charles Darwin University, Akhilesh Surja.

“With Tracy, what I am told is that the speed was so strong that not a single leaf on trees remained,” he said.

“Not just that, but all the birds were gone. It was a deserted town.

“Because of that, replantation and growing something very fast was certainly a need, and from what I read trees that were chosen [like the African mahogany] required little management in terms of the growth of the tree.”

The chosen trees had dense foliage and grew quickly.

Associate Professor Surja said there should have been more respect paid to local vegetation and local Indigenous knowledge.

“Indigenous knowledge and appreciating the knowledge of what kind of flora and fauna are resilient to cyclones and other natural hazards was not very well considered during the revegetation of Darwin after Tracy,” he said.

“We need to understand that people have been living in this part of the world for maybe 40,000 to 50,000 years if not more, and they do have lived experiences which should be prioritised when making these sorts of decisions.”

No point delaying replanting in case of another cyclone

Many Top Enders are still undertaking the arduous process of clearing debris, wood, and general damage from Cyclone Marcus, and Mr Lewis said the replanting of trees was an important part of the rebuilding process.

“Seeing the trees go in the ground is a really positive thing for the community, they can see Darwin start to recover and hopefully we can start to make some inroads into cooling and greening the city,” he said.

As for possible cyclones still to come, he said it was the right time to give the planting a go.

“That’s a risk you face every single year in Darwin,” he said.

“There’s no point delaying planting in case you get a cyclone, because you could get one at any point over the wet season, and it’s really better to establish a tree while there is some soil moisture and the chance of rain.”

Dr Surjan said that while preparing for infrastructure is important, it’s also crucial to remember that trees alone won’t save the city.

“We need to repackage the message of being prepared at all times to the people who live here for longer, but also to the new people, because Darwin and the Northern Territory have such a high turnover in populations,” he said.

“Complacency or ignorance of people to the risk of cyclones must change, and this requires constant effort and hand-holding, constant education, not only from council and Government, but the community.”

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Topics: government-and-politics, urban-development-and-planning, environment, horticulture, gardens, darwin-0800, nt

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