The Engineering, Printing and Manufacturing Union says Carter Holt Harvey has told its staff it plans to cut about 70 jobs in Rotorua and Tokoroa before Christmas.
The EPMU says the timber company is putting the job losses down to a fall in demand from export markets in Australia and a lack of new builds in New Zealand.
The union says the proposals include axing 18 positions at its Tokoroa plywood plant, and closing its Rotorua Profiles plant at a cost of more than 50 jobs - including contractors.
EPMU timber industry organise Ron Angel says the company's difficulties are real.
"Dumping into Australia has certainly affected a lot of their manufacturing there, and then the lack of the rebuild in Christchurch and other housing in New Zealand has also been just the last straw for them."
Mr Angel says he lives in Christchurch and the big rebuild is just not starting.