"I had a chainsaw wrapped against my stomach," he said. "The chainsaw was running but the bar on the chain was not moving. It did shake me up quite considerably."
He then rang police again to make a formal complaint, which police are investigating.
However the developer's agent denied Morison's claims about the incident.
"The tenant and his son drove a truck and tractor in front of the tree and then started pushing a contractor, who stopped immediately and left the site. The police were called by the developers' agent," said Mat Peters, head of design and development at Special Projects Team.
He also questioned claims that the Norfolk pine in question was planted by James Snell.
"The removal of the Norfolk pine was carefully considered by architects, iwi, an ecologist, and an historian contracted to research the history of the tree," Peters said.
"The historical study found no recorded history of the tree's planting, and concluded it may have been self-seeded from other trees in the area."
Another resident, Michele MacKenzie, said she went to the scene as soon as Morison told her that the contractors had arrived this morning.
"The contractors are standing on the side of the drive. We are waiting for the area commander of the police," she said.
"The police did want to remove us. However we are guests of the tenant, therefore we have a right to be here."
Peters said the developers were committed to "working constructively with authorities to resolve this dispute so that we can get on with the lawful removal of the Norfolk pine".
"This work will not only benefit the residential development, but the overall Snells Beach environment."
Rodney Local Board chairwoman Beth Houlbrooke said her board was not informed of the resource consent application before Auckland Council officers decided not to notify it publicly.
"That step was omitted and we are told it was an oversight. That is concerning, and we are making sure that doesn't happen again," she said.
She has appealed to the developers for a "stay of execution" to give residents a chance to be heard.
But she said the Norfolk pine was not a scheduled tree and was on private property, so she could not do anything to stop it being felled.
"I do believe in private property rights. It's on private property. You don't go on someone else's property," she said.