Vandals have been cutting down mature trees across Hobsons Bay and, in some cases, taking them away.
Five mature eucalyptus ironbark trees were cut down and removed from a reserve in Carinza Avenue, on the border of Seabrook and Altona Meadows, on August 3.
There have been similar acts at other reserves, including Altona Coastal Park and Truganina Park.
A large gum tree on the corner of Marion Street and Seventh Avenue in Altona North was cut down and left on August 1.
The actions have bewildered residents, who speculate that vandals may be posing as council workers and cutting down trees in broad daylight.
The council said its staff could be recognised by high-visibility uniforms bearing the city logo and by their marked vehicles.
Mayor Colleen Gates said the spate of tree vandalism was disturbing.
“These ongoing acts of vandalism across the municipality are very distressing, especially, in this instance, to the Seabrook and Altona Meadows communities,” she said.
“Our trees are so important to our community, to our local birdlife and other creatures, and to making our suburbs liveable, green and healthy.
“Sadly, this type of vandalism seem to be on the rise, with similar acts occurring in other reserves.
“We appreciate our community remaining vigilant in reporting suspicious behaviour or vandalism.”
Tree vandalism can be reported to the council on 99321000.