This area is home to a number of endemic plants especially in regions of Northland such as Cape Reinga and Te Paki which have at times been cut off from the rest of the island by high sea levels.

The ecoregion is named for its most notable endemic species, the impressive southern kauri trees, which can grow to 55m high and 20m round and has no lower branches but a long trunk of up to 30m and a wide crown.

This fertile area has long been the most populous part of New Zealand and the original kauri forest has mostly been removed.

The logging and gum-tapping that caused this has stopped now and much of the remaining kauri forest is now protected in the Northland region and on the Coromandel Peninsula.

Wildlife in the region is vulnerable to introduced predators such as the Polynesian rat, ferrets and stoats to the extent that the strongest remaining populations of many plants, birds and reptiles are on offshore islands rather than North Island itself.