City of Greater Bendigo arborist Brett Bain said a number of factors had escalated the internal decay of the trees and increased the possibility of large limbs dropping on people.

Mr Bain said the trees had experienced a history of being lopped at trunk height, so the main growth lines were not as structurally sound as natural branches.

"A recent storm tore down some large leader lines and that was the nail in the coffin for them. There is just too much liability and risk," he said.

"Then the crutches have also been chewed out by galahs for their nesting, which is entirely natural, but over time it weakens the tree and has the increased potential to drop limbs.

"This would be fine in a forest, but not here."

Mr Bains said it was difficult to establish if the drought had contributed to the weakening of the trees, but successive dry years tended to sap most native trees of their reserve food supplies and drought tolerance.

"Given their size and stature we have tried to maintain them as long as possible, but in this case the risk to park users was too great,"' he said.

"We will be removing them to trunk height due to the galah's nest, and when they have finished the season we will replant them with a stronger species."

Mr Bains said the native trees were not indigenous to Bendigo, but they had played an important part at the park and they would look to replace them as soon as possible.

The removal of the trees closed Havlin Street West between Mundy and Williamson Streets last week.