The incident happened in Roosevelt at about 4:30 p.m. on Wednesday, Jan. 12, the Nassau County Police Department reported.
NCPD said the workers were cutting elevated limbs and branches when a limb struck the man on the top of his head.
Police said the workers were using ropes to control the speed of the limbs as they came down.
The man had no pulse, and officers performed CPR, police said.
He reportedly lost and regained a pulse multiple times.
NCPD said the man was taken to a hospital and is listed in critical condition.
The investigation into the incident is ongoing.
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