Trees planted nearly a century ago by the man who transformed Canberra into the garden city will be removed for the second stage of light rail.
Twenty-eight trees on the Commonwealth Avenue median from Lake Burley Griffin to Coronation Avenue will be cut down for the extension of the network to Woden.
Details of light rail stage two released last week said the trees, which were "original Charles Weston 1920s cedar plantings" would be replaced "to provide the desired amenity for the Avenue for the next 100 years".
Around 40 new trees would be planted between the carriageways, 20 of those from Lake Burley Griffin and Coronation Drive.
The trees between Coronation Drive and King George Terrace would be kept and Commonwealth Avenue north of the lake would have trees for the first time, under the plan.
Charles Weston was Canberra's first afforestation officer and he transformed the city from an infertile, windy and rabbit-infested rural outpost into a city fit to be Australia's capital.
He spent 13 years experimenting with different breeds of seedlings to determine what could survive Canberra's climate, and by time he retired almost 1.2 million trees had been planted across the city.
Former National Capital Development Commission landscape architecture director Dr John Gray, who literally wrote the book on Charles Weston and his transformation of Canberra, said while the trees had a "chequered history", they should be saved if possible.
Dr Gray was also a vocal opponent of the removal of hundreds of trees on the Northbourne Avenue corridor for the first stage of light rail.
"Charles Weston planted those trees so as to reduce amount of wind coming into Parliamentary Triangle. They were planted fairly close to one another and in the 1960s the National Capital Development Commission decided to alter the landscape of Commonwealth Avenue and added English elms which are on the verges, not the median," Dr Gray said.
"The idea they had was the English elms, which would become very big, would eventually dominate the avenue and the avenue would then have the cedars removed, it would be a very large open boulevard. The median on the northern side of the bridge is open and they would open the median up on the southside so the bridge would look much the same as present as the median on the northside."
However the idea was abandoned, and the National Capital Authority said the trees have "acquired some heritage significance" in the intervening years.
Dr Gray said the ACT government was not working hard enough to retain the existing landscape of Canberra.
"If you want my personal view what I have difficulty with in all of this business is that the removal of existing trees in large avenues like this is unnecessary," he said.
"As we can see Northbourne Avenue is a mess at the moment, it's going to take a long time after that tram starts running for the landscape of Northbourne Avenue to recover so despite what the NCDC were doing all those years ago back in the 1960s talking about removing them I think every effort should be made to retain the trees now.
"I don't think engineers have given enough thought to the protection of avenue trees in Northbourne Avenue and if they're talking about removing trees in Commonwealth Avenue my comment would be the same."
Asked why these trees mattered when Charles Weston planted many, Dr Gray said it was a part of Canberra's history.
"In all of my work in Canberra I always tried to retain trees that had been planted by others before me. They take a long time to grow. They're an important part of our heritage. I think our landscape is too precious to be chopping away at it the way it's been done in Northbourne Avenue," Dr Gray said.
The ACT government said in its June update light rail presented an opportunity for a "place-based approach to the revitalisation of these trees, reinstating the character and history of the avenues".
They also noted the trees were assessed in 2013 to have a life expectancy of five to 40 years, and their replacement gave the government the opportunity to "strengthen the qualities of the Avenues and view corridors through the enhancement of tree plantings".
In its submission to the federal inquiry into light rail stage two, the National Capital Authority said while many trees planted by Charles Weston are proposed to be removed, others have been identified as being "subject to further impact assessment".
"The NCA could only consider the removal of trees with heritage significance if an appropriate reafforestation strategy was in place," the NCA wrote.