"They're just beautiful trees," she told the Rotorua Daily Post.
"I'd hate to think how old the trees are."
The library building is being renovated and would be reopened as a new library and health hub, with health services for children, later in the year.
An upgrade of Jean Batten Park would be part of the library revamp, with trampolines and play areas being added.
Ms Harford said in her view moving the trees would have been a far better solution if they impeded roadworks.
"They could've got an arborist in and replanted them somewhere else. One's just been hacked at."
New trees would be put in on either side of the road, the council said.
"The work that's under way is the construction of a large raised crossing to provide safe access between the library building and the carpark on the other side of the road," a council spokeswoman said.
"Four maple trees had to be removed and will be replaced with eight new trees on either side of the road.
"The work is expected to take a few months to complete and was publicised on council's website and via council social media."