Acting Sergeant Sue Robinson said the workplace accident was being investigated by police and the Ministry of Business Innovation and Employment.
"We don't really know what happened at this stage and we won't really find out until we get the coroner's reports back."
She said the 17-year-old could not be saved by emergency services when they arrived at the scene.
St John District operations manager Stephen Smith said two ambulances arrived at the orchard where paramedics attempted to resuscitate the teen.
A spokesperson for the Ministry of Business Innovation and Employment said an investigation had been launched and two health and safety inspectors were at the orchard yesterday.
The police Serious Crash Unit is also investigating on behalf of the coroner.
Tributes for the dead teenager and his grieving family were posted on Facebook yesterday.
"I want to absorb some of your pain, so much love to you and everyone involved, I can't even imagine what your going through my girl," said one.
"Love to you and your family, poor little bugger," said another.
"I can't even begin to imagine what you are going through.
"You and your family are in my thoughts."
The tragedy follows another workplace fatality in May, when 53-year-old Jeffrey McCulloch, a local construction worker, was killed at the former Farmer's site on Emerson St, Napier, after being struck by a large steel beam.
Charges have since been laid in relation to the death of the foreman, the Ministry of Business, Innovation and Employment confirmed last week.