Sydney Trains has amended plans to manage trees along the rail corridor, but the potential impact on the tree canopy in Sutherland Shire remains a major concern for the council.
Sutherland Shire Council has written to the rail authority, saying changes to the 2018 draft plan don't go far enough and called on it to "recognise the contribution of trees to local biodiversity and resident amenity".
Large fig trees close to the line at Sutherland station would be among trees that would be cut down under the proposal.
Cr Ray Plibersek told the council meeting on Monday night Sydney Trains had adopted "a cowboy like attitude to tree clearing".
Cr Diedree Steinwall said the plan was "shocking and excessive", and the impact on the shire would be "devastating".
"I drove from Heathcote tonight and looked at all the trees along the train line, and particularly the fig trees at Sutherland station, that would be lost," she said.
The meeting endorsed a previously submitted submission by council staff calling for further changes and added that Sydney Trains should commit to a replacement policy of four new trees for every one that is removed.
State MPs in the shire will be asked to make representations.
A staff report said, under the revised draft plan, trees may be removed by Sydney Trains where they are a risk to the network, on the advice of a consulting arborist, and Sydney Trains may undertake replanting where appropriate.
"A minimum three metre clearance space is required around the electrical distribution network," the report said.
"The plan proposes to minimise visual impacts while maintaining necessary clearances.
"The plan still requires all new trees (trunk) be setback at least 10 metres from the network or at a distance equal to the mature height of the tree, whichever is greater.
"This is considered excessive and far exceeds the requirements of Ausgrid."
The report said Sydney Trains would be able to undertake vegetation management as exempt development, without any requirement for further environmental consideration.
"The plan does not recognise that appropriate species selection and formative pruning can allow trees to grow that will not interfere with the distribution network," the report said.
"It is considered that a 10 metre setback will result in significant canopy loss in the shire.
"If all other network carriers applied this policy, there would be no almost street trees.
"This approach overestimates the potential risks at the expense of amenity and biodiversity.
"The plan encourages replacement planting, but does not commit to tree replacement planting.
"The plan states that Sydney trains may negotiate the replacement of 'only those trees in existence prior to the construction of the feeder'".
"The local feeder lines are estimated to have been constructed in 1926 and 1939."