MP for Te Tai Tokerau Kelvin Davis is urging whānau to oppose moves to allow genetically modified pine trees in the north.
Submissions close today on a National Environment Standard proposed by the Ministry for Primary Industries that would let plantation foresters use GM tree stock.
Mr Davis said that one clause would override all the work done by councils from Auckland to the Far North to restrict the use of genetically-altered plants in their rohe.
He said it was of additional concern to Maori, as kaitiaki of native forests.
The ministry's standard would allow genetically modified tree stock approved by the Environmental Protection Authority, under hazardous substances legislation.
But Mr Davis said there were still too many unknowns about GM plants and their potential to cross-pollinate other species.
He said the government should respect rather than undermine the views of communities that wish to take a more precautionary approach.
Submissions to the Ministry for Primary Industries on the proposal close at 5pm today.