The Aleppo pine, grown from a seed of Gallipoli's famous original Lone Pine, has been a feature of the front garden of the Legacy villas in Albany Street for many years.
But the tree is now seriously ill, with one whole side of the tree looking withered and dying.
War widows living in the villas said the tree had been fading for more than a decade.
Resident Kath Cochrane said her daughter had taken seeds to a nursery at Alstonville but had been unable to get them to germinate.
A plaque at the base of the tree says it was grown in the Jubilee year of 1968 and planted in memory of departed comrades.
The villas were opened in 1966.
The president of the Coffs Harbour branch of Legacy, Graham Stubbington, said they had taken six nuts from the tree and sent them to the Botanic Garden to try to propagate a seedling.
Mr Stubbington said they had already pruned the tree back to try to rejuvenate it and would have to prune it further, but had now pinned their hopes on a young descendant.
He said he was not surprised the tree was sick because the Coffs Harbour climate was very different to Gallipoli.
"I've been to Lone Pine and it is very, very dry," he said.
Lone Pine, one of the ridges at Gallipoli, was given its name because the Turkish troops had chopped down every tree but one to make roofs for their trenches.
It was the site of fierce hand to hand fighting.
Seven of the 10 Victoria Crosses won by Australian soldiers at Gallipoli were won on Lone Pine, a rare Allied victory won at great cost.
In the four days of fighting which saw the Anzacs capture the ridge in August 1915, the Australians lost more than 2000 men, and the Turks 7000.
The battle had taken place in an area the size of two soccer fields.
Two of the soldiers souvenired pine cones from the ridge and sent them home to Australia.