Network Rail is planning to spend weeks removing lineside trees in Upminster but said there will not be any line closures.
The work is due to happen on the Romford to Upminster London Overground branch line and the railway infrastructure company has written to nearby residents informing them of the plans.
In the letter, seen by the Recorder, Network Rail said its staff will take away "overgrown" trees and vegetation next to the railway.
Dates are yet to be confirmed for the work, which is set to take place some time before the end of March.
The letter reads: "We only cut back or remove vegetation when there's a risk to our neighbours' property or the railway, which sadly was the case on the branch line between Romford and Upminster.
"We identified risk from trees falling on the rails, overhead lines or trains, and autumnal leaf fall, which can affect a train's braking ability."
Network Rail intends to hold a community meeting with residents about the plans, which it said are still being finalised, and said it will write to neighbours again with the confirmed dates of the work.
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