After crossing Whakapapanui Stream at the top end of the Whakapapa Holiday Park, the track meanders through beech forest. Pass the Whakapapanui Track turn-off and continue towards Silica Rapids. The track soon crosses a bubbling stream with a gold-toned bed. The coloured deposits are ironoxide clays from upstream swamps. Coprosma, five finger and broadleaf surround the track.
Emerging from the bush, the track climbs to a swampy area of wire rush, tangle fern and red tussock. Seepage ponds beside the boardwalk are home to freshwater crayfish (kōura). The boardwalk makes walking over swampy ground more comfortable and reduces the impact of foot traffic on delicate vegetation. This is a
great place to enjoy mountain views.
After passing the Whakapapaiti Track turn-off, the track follows the stream up through dense bush to Punaruku Falls. Here, after heavy rain, Tawhainui Stream tumbles over the edge of an ancient lava flow. Close to the track, metal bands on tree trunks protect mistletoe from possums. At the forest edge gold-coloured snow tōtara and olive-green bog pine give way to sun-loving alpine herbs and alpine flowers like mountain daisies, harebells and ourisia.
A little further up the hill the stream bed widens and forms a series of shallow terraces coated in creamy white deposits – the famous Silica Rapids. When the stream emerges from lava cliffs at the head of the valley the water is rich in aluminium and silicate minerals. As the stream gathers speed and the water is aerated, the alumino-silicates are deposited on the stream bed.
Moving on from the rapids, the track climbs onto a tussock-covered lava flow. A small clump of mountain beech and toatoa, seen a short distance up the mountain, forms the upper limit of beech trees in the area. The track then winds through tussock and sub-alpine shrubs.
Loop back to the start of the track by going along Bruce Road.
