Trees at Walkers Lake have been illegally lopped or cut in recent days and Northern Grampians Shire Council is asking people to dob in whoever did the cutting.
The council suspects the trees were cut by people selling the wood off-site for firewood.
A penalty of up to $1600 applies to anyone illegally gathering firewood outside of the designated collection areas within the shire.
Northern Grampians Shire Council Mayor, Murray Emerson, said illegally cutting trees was a serious offence.
"The trees and vegetation in our shire, especially around our lakes and waterways, form an important part of the ecosystem that wildlife and other vegetation rely on," he said.
"When these trees are cut or damaged, it impacts the wider ecosystem and disrupts the lives of the plants and animals that live in that ecosystem.
"We can monitor the areas but it is difficult for council to catch people in the act of damaging these trees so we rely on information from the general public.
"If you see someone damaging plants or trees at Walkers Lake, or anywhere in the shire outside of the designated firewood collection areas, report it to our community safety team."
You can find out where to legally collect firewood at the Forest Fire Management Victoria website.
Council's community safety team can be contacted via phone on 03 5358 8700 or email ngshire@ ngshire.vic.gov.au.
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