On Wednesday, council property and infrastructure manager Peter Hansby said the assessment showed there were no birds nesting in the trees.
"The location of these particular eucalypts, part way up a steep bank, made it impossible to build the necessary footpaths without weakening the root structure of the trees to a point where they become dangerous."
Another 47 trees would be planted along the street, which would become a "significant pedestrian boulevard" linking the town centre with tourism attractions, accommodation and the nearby Lakeview development, Hansby said.
By yesterday afternoon, Gibson Tree Care workers had removed two of the trees.
A local arborist contacted the Mountain Scene last month to say his company and two other local contractors had refused to quote for the work on ethical grounds.
Their stand was supported by Forest & Bird Otago-Southland and the New Zealand Arboricultural Association, whose secretary, Mark Roberts, described the trees' removal as "intergenerational theft".
Two online petitions calling for them to be saved had received a total of more than 1300 signatures by yesterday.
Queenstown resident Brigid Inder told the Otago Daily Times she was in a small group which watched workers begin removing the trees yesterday morning.
She laid a wreath beneath the trees before the work started.
Inder said her 89-year-old mother remembered them from her youth.
The felling "flies in the face" of the council's climate emergency declaration two years ago.
"It doesn't make sense to be cutting down mature, healthy hardwood trees in a climate crisis," Inder said.
"And they're beautiful."
Planners needed to design projects to incorporate the natural environment, she said.
