The Auckland Council is due to close much of the Waitākere Ranges today to protect kauri trees from dieback disease.
The forested areas of the regional park and some other tracks in the Hunua Ranges are meant to be off limits to the public from today.
The decision was made by councillors last month.
They also approved $740,000 to fund an enforcement programme involving two full-time staff, barriers and signs.
The council is expected to make an announcement this morning about managing the closure.
Councillor Penny Hulse said negotiations were continuing with local iwi about the closures.