Mr Henare had been allowed to enter a danger zone at the same time that another worker was using the loader to stack logs on the landing above him, Judge Tony Adeane found.
The work Mr Henare was doing was inherently dangerous, and HarvestPro had a duty to do more to protect his safety, WorkSafe New Zealand's general manager of health and safety operations Ona de Rooy said.
"Much of the forestry work in New Zealand is done on steep hillsides. It is not just the felling of trees that is dangerous - workers are at risk whenever logs are being handled and moved.
"WorkSafe NZ is working hard with the forestry industry to improve safety standards across the board. Our inspectors have carried out more than 220 inspections of log removal operations since August and issued almost 300 enforcement notices, including 25 prohibition notices."
The decision sent a "clear message to the industry".
HarvestPro was fined $80,000 and ordered to pay reparations of $40,000.