Orange’s Elm Trees are already reaping the benefits of treatment by Orange City Council tree crews to combat the spread of Elm Leaf Beetle.
Orange’s Elm Trees were badly damaged in 2017 after an unprecedented attack from the Elm Leaf Beetle.
The swarms of beetles ate the trees’ leaves which would normally be green and full during Summer. The trees then shed most of their leaves, leaving piles of skeletonized leaves on the ground. The early loss of leaves impacts on the tree’s ability to produce ( through photosynthesis) its stores of energy to grow and
In August 2017, Orange City Council’s Tree Crew treated about 260 trees, in streets and parks, with insecticide designed to kill the beetles once the insect had eaten the leaves.
While there are already positive signs, Orange Mayor Reg Kidd, said the full impact of the treatment against the beetle won’t be fully realised until at least 2019.
“The beetles must ingest the poison to be affected by it, “he said.
“This means they must still take a bite from the leaves, so people will still see leaves that have a shot hole appearance (adult beetle damage) or skeletenisation (eating away of the leaf surface between the veins by the larvae) about the place. The treatment works against both the adult beetle and larvae stages. “Already, residents are reporting far fewer damaged than last season. We’re already seeing an impact.
“Long term, this treatment is interrupting the lifecycle of the beetle, which means by this time next year\many of the beetles would have died before they had a chance to lay their eggs and we should see a much better result.
“We can’t treat every single Elm Tree in the city so we won’t ever be rid of this pest but we can treat as many on council property as possible.”
Cr Kidd said residents should seek advice from a professional arborist about how best to treat their own trees.
“It would be great if everyone in the city who has an Elm tree in their backyard could get some advice from a local arborist on how best to make sure their own tree stays healthy.
“Let’s band together as a community and do as much as we can to help keep our Elms looking beautiful.”
Council staff injected the trunks of about 60 street trees with insecticide last Spring, and treated a further 200 trees in local parks with tablets placed in the ground.
The insecticide within the tablets, dissolves within the ground near the feeding roots of the tree and then the sap flow takes the insecticide up to the leaves.
This technique works best in Spring as the tree starts to bud.
Injections straight into the trunk work much faster, generally within 48 hours, however this method is more expensive.