Council, Swan, Bruce, Bull and Laman streets will be among the first to lose their ageing trees, many of which are causing serious problems in the area.

Newcastle city arborist Philip Hewett said planning for the trees' replacements would be combined with a community information program over the next two years.

"We have got to start looking at where the greatest need is; Council Street has massive problems with infrastructure," Mr Hewett said.

"We want to combine the job of getting the big trees out, dealing with the root systems, utilities and building planes."

Mr Hewett briefed Newcastle councillors last week about the condition of the city's trees, many of which will probably need to be removed over the next 15 to 20 years.

In many instances, ageing branches have become an insurance liability.

"No one is enjoying the fact that this needs to be done, but the reality is that we need to act out of necessity," Mr Hewett said.

He has recommended against trying to replace two large Hill's figs in Laman Street.

"I pointed out that you can't put avenues back in pieces," he said.

"We can't afford to put trees in when we have to deal with a much bigger issue first."

Mr Hewett said the future form of the Civic cultural precinct needed to be resolved before a discussion could be held about the most suitable tree stock.

"I'm interested for people who want to design that space to tell me what they want then we can go away and find a tree to suit," he said. "Whatever tree you put in there, it has to tolerate very difficult conditions."