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Hyde Park trees: Fight to save trees could cost millions as concern grows

An outbreak of a tiny beetle killing thousands of Perth’s trees could cost many millions of dollars to eradicate, with experts warning it’s Australia’s worst biosecurity threat in decades. The polyphagous shot-hole borer has been found in more than 6000 Perth trees in a quarantine zone of almost 200 suburbs, putting the State’s urban tree canopy and agricultural sector in jeopardy. WA’s peak local government body has launched a campaign calling for a “fighting fund” to help councils pay for the removal and replacement of infected trees. Just 2mm long, the pest burrows into trees and, to feed its young, releases fungus which stifles water and nutrient flow. There’s no known cure and affected trees can die within two years. The City of Vincent has put a value of $9 million on the almost 200 infected trees in Hyde Park, which includes well-loved Moreton Bay figs. Pruning branches can stop the spread in some cases but if the trunk is infected, the entire tree will be removed. More than 3000 trees across the city have been axed and chipped with the contaminated matter sent to a site in Jandakot for hot composting. A 163-strong team, established in the Department of Primary Industries and Regional Development, has been scrambling to contain the destructive borer since it was first detected in 2021 in Fremantle. But the pace of the response has been slammed, with the Western Australian Local Government Association this week meeting Agriculture Minister Jackie Jarvis in the hope of more action. WALGA president Karen Chappel warned the outbreak was “at a tipping point”. “The Government must increase efforts to contain and eradicate the borer, as well as prioritising replacing the thousands of trees already lost,” Ms Chappel told The Sunday Times. City of Vincent mayor Alison Xamon expressed concern over the slow pace of tree removal. Dozens of Hyde Park trees were supposed to be removed over winter, but the council has been at the mercy of a State Government red tape approvals process to start the chainsaw. “In late May 2024, DPIRD’s work was put on hold while required approvals from various agencies were obtained,” Ms Xamon said. Half of the City of Perth’s 16,000 trees are at risk, according to Lord Mayor Basil Zempilas, who called the outbreak “COVID for trees”. “The State Government have been woefully behind on this issue. This is the greatest biosecurity emergency facing WA today,” Mr Zempilas said. Ms Jarvis argued that DPIRD was taking a “careful approach”. “It’s a staged approach to actually make sure that it’s well managed and that we’re dealing with the biosecurity waste management once we chop up the tree in a careful manner,” she said. “Arborists will move from one side to the other.” She played down concerns that procurement issues and a shortage of arborists had contributed to the delay. The City of Perth has started removing some infected street trees at its own cost after waiting months for the department to act. Mr Zempilas said the pest had also been detected in a large, century-old fig between the Council House and Supreme Court, valued at more than $750,000. “The effects are having multigenerational impacts to iconic green spaces throughout the metro area,” he said. “We could lose all of the trees in Supreme Court Gardens.” WA hotspots include Kings Park, Lake Claremont, Rottnest Island (Wadjemup), Perth Zoo, Hyde Park, and Balbuk Reserve in Burswood. The box elder maple, Moreton Bay fig, and Port Jackson fig are most susceptible to the borer. The global host tree list has grown to more than 500 species, of which 130 are in WA. The borer has mostly targeted introduced species in Perth, but more recently, more than 30 native species have been added to its host list. In May, Ms Chappel wrote to Premier Roger Cook to say that concern held by the councils “cannot be overstated”. “We need the State to step up to help councils, households and individual property owners replace PSHB-affected trees,” she said. Canning mayor Patrick Hall said 18,000 at-risk trees had been identified in his city and more than 100 had been removed. Cr Hall said it should not be left to council ratepayers to fund the Statewide response. “I’m really disturbed about the lack of activity and the lack of a sense of urgency, from the Government and from the department,” he said. “We’re seeing a lack of action, but mostly a lack of funding. Fighting funds should be set up.” Ms Jarvis acknowledged it was “heart-wrenching” for Perth to lose old beloved trees and it could be a “massive cost” for councils. “I understand people are frustrated and there will be significant cost to local governments,” the minister said. “We still don’t know what recovery costs (will be) because we don’t know how many trees will have to be cut down. “That’s a decision for the future. We’re still in the middle of an emergency.” Shadow environment minister Neil Thomson questioned whether the situation was already unmanageable. “We didn’t go hard enough, early enough,” the Liberal MP said. “This has been around for three years. The question is, has government lost control of this? “They still claim that they’re going to eradicate it. I hope they can, but I just can’t see how as it’s so entrenched in so many locations.” He also slammed the department for not launching a public awareness campaign earlier. There appears to be little difference in figures recording the department’s eradication efforts between May and July. According to provided figures, fewer than 100 trees were axed in that period despite the thousands earmarked to go and the number pruned dropping by 60. The department, however, told The Sunday Times it wasn’t through lack of activity — but rather because the surveillance data has been “revised”. WA’s outbreak has slowed due to the borer being less active in the cooler winter weather. But independent environmental scientist Peter Keating said it could erupt again in spring as temperatures increase. Dr Keating said he would like to see future research into the correlation between Perth’s hot, dry summer and the spread of the borer. With forests and shrubland dying over WA’s record-breaking dry spell in the past year, he said much of the tree canopy cover would have already been damaged, likely providing a better environment for borers to dig in and release fungus for their offspring. “We’ve had the driest hottest spell on record,” Dr Keating said. “A lot of these trees are all showing stress symptoms. I believe it has increased threats.” But Ms Jarvis said she had “full confidence” in her department that every option was being undertaken. “At this stage, we need to eradicate it,” she said. “If we stopped felling now, if we throw our hands up and say; ‘we can’t (reach) eradication’, all these trees die anyway. “In California, for example, they didn’t get on to it early enough and they weren’t able to eradicate the pest and it cost their economy billions of dollars every year. So, we know that cost is significant. “That’s why we’re throwing everything in the eradication plan.” Department deputy director-general Mia Carbon added: “DPIRD is working closely with local governments, traditional owners and the wider community to keep them informed of actions being taken to contain the spread of (the borer) and protect Perth’s urban tree canopy”. UWA associate professor Theo Evans said establishing what financial impact an infestation could have on the economy, especially the agricultural sector, would be an important step to encourage further investment and more immediacy is placed on tackling the outbreak. Most of the Perth metro area is in the 871sqkm quarantine area, which spans 25 councils including Armadale, Joondalup, Cockburn, and Cottesloe. Perth residents can’t move bark, firewood, prunings, logs, plant cuttings, mulch, or wood out of the quarantine zone, and if borer impacted material is found it must stay on premises. The borer to date has not been detected outside the Perth metropolitan area. The heart of the city’s western suburbs, Nedlands and Claremont, have been hardest hit — with 345 and 105 infected locations, respectively, while 158 have been detected in Melville. While female borers have been found to fly 400m, Professor Evans said the biggest threat was humans transporting contaminated material long distances. In July, the department’s team travelled more than one million kilometres and inspected about 1.8 million trees on nearly 60,000 premises. The Federal Consultative Committee on Emergency Plant Pests toured Perth over three days this week, inspecting several affected sites and meeting with WA teams tackling the issue. Federal Agriculture Minister Murray Watt said he received regular updates from the committee on the situation in WA and Commonwealth funding was continuing to aid the eradication efforts. “The Albanese Government has committed up to $20m as part of a joint effort of $41.29m to contain and eradicate the current outbreak of polyphagous shot-hole borers under the Emergency Plant Pest Response Deed,” he said. “This funding is continuing to assist the WA Government lead the efforts.” The City of Vincent’s estimate accounts for almost one-quarter of the three-year $41.29m national response plan, to which the Federal and all State and Territory governments have all contributed. Among the future costs, the city expects a bill of $360,000 for park rehabilitation, $250,000 for more than 12,000sqm of canopy and garden restoration and $150,000 a year in further maintenance needs. It estimates it will take more than two decades to replace the loss of shade in the park. Asked if the cutting of trees at Perth Zoo could affect the broader ecosystem of the area, a spokeswoman said impacts has so far been minimal. “Since the pest was detected, we have had 78 trees removed and 87 pruned,” she said. “The impacts to the site, to date, have been minimal. “Replanting activities have been taking place using mature trees. “We are working through the best ways to manage the trees in animal areas to ensure they always have appropriate foliage and habitats.” The polyphagous shot-hole borer’s first invasion was identified in Southern California in 2003, and since then, in Hawaii in 2007, Israel in 2009, South Africa in 2017, and Argentina last year. Professor Evans encouraged the department to invite to Perth experts from previously affected areas to help assess the situation. He also questioned the level of professional arboriculture input informing the department and urged the agency to use all available resources. “There is also a lack of an entomologist, and this isn’t just true in WA, it’s across Australia,” he said, referring to the professional scientific study of insects. “A lot of technical expert jobs have vanished in State Government departments. There are whole areas of expertise that have disappeared entirely. And that’s a long-term problem. It’s not just one government that’s done this. It’s happened over decades.” Many councils not wanting to sit idle have undertaken their own research and monitoring. The City of Perth has started mapping all trees and 3D scanning those deemed a priority, to easily monitor the progress of infection on branches . They have also proposed their own research project but would be restricted by quarantine protocols that would block infected material being transported to a lab. Dr Keating and Professor Evans said no exemptions for scientific research under the quarantine protocol made it difficult for eager accredited experts to help. “We’ve been discussing ideas with different city councils to see if we can run experiments in their trees that they are managing but it’s almost impossible to do work on this beetle in WA,” Professor Evans said. “Essentially you cannot move, infested material or the beetles away from where they were discovered.” Councils in Victoria and New Zealand have even contacted the city for information and advice. Locals are struggling to comprehend the magnitude of the problem. Julia Sewell lives near Hyde Park and walks her dog, Sebastian, there almost every day. She said it was “horrific” the trees couldn’t be saved. “I’m disappointed, I guess, because especially in the summer it adds a lot of shade and we walk here and we love it,” she said. Margaret White also lives nearby and she and Bayswater resident Eleanor Hunter enjoy meeting in Hyde Park to catch up over a coffee. They say they have been visiting more often to enjoy the trees more before they are felled. “I’m devastated. We come down quite often just to see them in case they do cut them down soon,” Ms White said. Ms Hunter said the removal of trees would highlight the importance of biosecurity measures at entry points to WA. “People have been coming here for more than 150 years, it’s a park that’s in a Perthite’s soul,” Ms Hunter said. “It’ll be devastating to see. We seem to have had in the last couple of years far more foreign biodiversity threats. “Already, Perth has got the lowest tree canopy. It’s embarrassing and should be something we’re ashamed of.” In other jurisdictions, apple, avocado, macadamia and mango producers have reported issues with the beetle. Pomewest executive manager Nardia Stacy said, despite the borer being detected in the Perth Hills — the site of many orchards — no producer had yet reported the borer. “I understand no producers have been impacted so far. I would urge producers to check their insurance policies,” she said. Fruit West co-operative director and Sunpick Orchards manager Mark Wilkinson has been following international developments. “My best guess from overseas incursion is that the apples and stone fruit are not favoured hosts and do not support PSHB breeding. Stressed and weak trees may be affected,” he said. Under emergency laws for the eradication program, the department can act on land deemed culturally significant. Despite this and the borer only being detected in the metropolitan area, councils in the Goldfields and Esperance regions have raised concerns over potential delays in eradication programs due to Aboriginal cultural heritage approvals processes. The State Government has dismissed those concerns, with a spokeswoman saying no works had been delayed. “DPIRD has also been consulting closely with the Whadjuk Aboriginal Corporation to ensure Aboriginal cultural heritage is preserved on any significant site,” she said. Environmental lawyer Bronwyn Waugh said she feared solely attempting to quarantine as opposed to investigating treatment opportunities could further put Perth’s tree canopy at risk. The South Perth Liberal candidate will host a summit on the issue next month, saying it was front of mind for people in her leafy seat, with large mature trees lining streets and adding to the character of the area. Back in Hyde Park, visitors worry about its future. Scarborough local Claire Charman appreciates its scenery and visits to enjoy a book, but couldn’t imagine Hyde Park without its trees. “It’s nice and green, relaxing, and quiet,” she said. “I think we’re really lucky with Kings Park but I like coming here because it’s much more quiet.” Yokine neighbours Lara Hafza and Julianna Love often walk in the park and enjoy a treat from nearby Chu Bakery. “We have lots and lots of memories here. I can’t imagine them cut down, you associate Hyde Park with the trees,” Ms Hafza said. “It’s sad,” Ms Love added. “My sister even had her baby shower here. And friends used to always have barbecues here every Sunday.” About a year ago, Hyde Park was a key factor that enticed Martin Nikoloski to buy a house nearby. “I come fairly often,” he said. “Perth doesn’t have a whole lot of parks, so this is such a special place for a lot of people around here. People buy property just to be closer to this park.” “Some of the trees are well over a century old. You can’t put a price on it. They’re irreplaceable.” More than 3600 borer reports have been made to the MyPestGuide Reporter App since an East Fremantle resident made the first discovery in August 2021. People are urged to use the app if they detect the beetle.

exclusiveHyde Park trees: Fight to save trees could cost millions as concern grows

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Hyde Park trees: Fight to save trees could cost millions as concern grows