Penrith City Council has been assessing all spotted and peppermint gums in public spaces, with a view to remove potentially unsafe trees.

The removal of trees will begin this month.

Former mayor Jim Aitken said last month there were many trees with shallow roots along footpaths.

``Shallow roots can cause uneven footpaths, and damage underground pipes, fences and even house foundations,'' he said.

He said wherever a tree was cut down, every effort would be made to replace it with a more suitable tree.

A council spokesman said many of the trees were planted up to 30 years ago, when there were a lot fewer footpaths and less kerbing and guttering.

``The problem is that when placed between footpaths and kerbs there is insufficient space for tree roots,'' he said.

He said the tree removal was part of five-year program to pull out these types of trees mainly from nature strips, with $304,000 allocated in this financial year's budget.

The spokesman said the trees may not be replaced straight away, depending on the best season for planting.

The Eucalyptus nicholii species is listed as vulnerable, but the spokesman said the trees the council were removing were not part of an endangered ecological community as might be found in a natural area or reserve.

``The removed trees are also mature and near the end of their life as a street tree,'' he said. ``We must manage them to reduce public risk.''

Penrith City Council plants about 20,000 trees a year.