Trust chairman Jim McQuillan said the reserve had been inundated with species such as barberry and sycamore.
The trust would begin its work around Gerry’s Rock, where the best view of the harbour could be found, and slowly expand further outward, he said.
The group was reaching out for community support at a public meeting at the Ravensbourne Hall on Sunday at 3pm.
The meeting would help people understand what the group’s aims were, he said.
"Many of us enjoy getting into the bush. It’s almost a therapeutic experience."
"A lot of Signal Hill has gone to cyclists and pedestrians can’t go there because they would be risking being run down by a bike."
A long-term aim for the group was to improve access to the reserve from the harbour side.
The group would also survey the area to understand what native flora and fauna were there and what needed to be done to protect it.
They had targeted a group work day for March 16 and were hoping members of the public would join, especially young people, Mr McQuillan said.
