More police are being brought in to prevent trouble flaring as tree felling resumes in Sheffield a month after violent clashes brought it to a halt.
Sheffield council and contractors Amey put a temporary stop to work in January to allow for a safety review.
It followed clashes between campaigners and workers with one contract worker suffering a broken wrist.
Police said there would no longer be a "low key presence" at sites and it would not tolerate disorder.
The council, which is planting new trees after removing existing ones, insists the trees earmarked for felling are either "dangerous, dead, diseased, dying, damaging or discriminatory".
However, campaigners dispute this and say many of the trees could and should be saved. They want amendments made to the surrounding pavements and roads instead.
Trouble escalated on Meersbrook Park Road last month with claims both workers and campaigners had been assaulted.
South Yorkshire Police said there had been a number of arrests in relation to the disorder with more to come.
David Hartley, assistant chief constable, said: "We're here to remain absolutely fiercely independent and just keep everyone safe."