The air and soil temperatures in Tongariro National Park change dramatically with the seasons; the result is a wide variety of habitats.
Anything that lives in the Tongariro National Park must be hardy and well-adapted to life in such an extreme environment.
As well as continually changing air and soil conditions, plant life has to contend with volcanic activity - ash lahars, pumice, lava and fire, which can destroy entire landscapes.
In the event of an eruption, it can take a very long time for plants to re-establish themselves especially if the soil has been covered with lava.
Beech forests once covered the northern slopes of Mt Tongariro, but the result of multiple eruptions and subsequent fires, means only red tussock and small shrubs survive on the upper slopes while the low level forest is made up of totara trees.
In damper areas on the northern slopes of the mountain, above Ketetahi, you can find mountain buttercups and the large mountain daises in summer.
A native bird species called pipit nests in the tussocks. They are often seen looking for cicadas and grasshoppers as prey. In the forest, also on the northern slopes of the mountain you may see a north island robin.
It is important to keep to the marked track as plants take a long time to grow on the mountain. The soils are fragile and the balance of life can be easily disturbed.