IN FEBRUARY 1839, pioneer European explorer and botanist John Bidwill journeyed to the centre of the North Island. Here he encountered “frost flats” for the first time, something he described in Rambles in New Zealand: “As we went on, the land became more and more barren and level, till it became a mere moor, without a shrub, and almost without vegetation; a few bushes of the miserable-looking Dracophyllum being all that occurred to break the monotony of the plain.”

New Zealand’s most famous short-story writer, Katherine Mansfield, after a coach trip in November 1907 from Napier to Rangitaiki and Galatea, across the desolate high plains of the Kaingaroa plateau, wrote in The Woman at the Store:
All day long the heat was terrible. The wind blew close to the ground; it rooted among the tussock grass, slithered along the road, so that the white pumice dust swirled in our faces, settled and sifted over us and was like a dry-skin itching for growth on our bodies. The horses stumbled along, coughing and chuffing... Hundreds of larks shrilled; the sky was slate colour, and the sound of the larks reminded me of slate pencils scraping over its surface. There was nothing to be seen but wave after wave of tussock grass, patched with purple orchids and manuka bushes covered with thick spider webs.

A hundred years later, the landscape presents a vastly different prospect to the traveller. The rutted pumice track has become a modern high-speed state highway. The native tussock and manuka have been largely replaced by a firebreak fringe of scrawny grass, backed by mile after mile of sombre radiata pine relieved at intervals by groves of feeble eucalypts, an attempt by the late New Zealand Forest Service at roadside beautification. In other places, sheep graze on sparse pasture, and, increasingly, dairy herds on lush swards of ryegrass and clover. Only the heat is still there, and the skylarks. On clear summer days, this is about as continental a climate as one finds in the North Island.

Yet, remarkably, just a short distance off State Highway 5, close to the northern foothills of the Ahimanawa Range, a piece of the landscape encountered by early travellers and described so vividly by Katherine Mansfield has survived nearly a century of land development in the region. This is Rangitaiki Conservation Area, a corner forgotten after its abandonment by farmers in the early 1920s until its rediscovery by scientists of the Forest Research Institute (FRI) in Rotorua in the mid-1980s.

John Nicholls, responsible for promoting the idea of a nationwide network of reserves within the then state forests, was poring over early black-and-white aerial photographs of the region one autumn afternoon when he identified what appeared to be a great tract of short scrub around the upper reaches of the Rangitaiki River. Wondering if it was an area that had escaped the effects of the decades of forestry expansion over so much of that part of the country, he collared a fellow scientist and drove down there a few days later. To the two men’s amazement, as they crossed the low saddle that separated the area from the highway, they were greeted by a vast expanse of red-brown monoao (Dracophyllum subulatum) shrubland, the largest and best surviving example either had seen of frost flats, an ecosystem that once stretched over thousands of hectares of the volcanic plateau but by then had all but disappeared.