Climate Change Minister James Shaw has taken the axe ... to farmer estimates of land being converted for forestry

Farmers have said up to 70 thousand hectares are being lost a year to meet carbon-zero targets.

Shaw says those numbers are wrong - and he's not worried that tree planting is impacting food production.

He says only 13 thousand hectares were planted last year.

Shaw says farmers have genuine concerns, however, in parts of the country and the Government is looking into planting rates.

Tree planting reached a 1994 peak of 98 thousand hectares.