Vulcanicity and vegetation in the Rotorua district: Vulcanicity and indigenous vegetation in the Rotorua district

[First paragraphs...]
Although most of the country round Rotorua is climatically and edaphically suitable for forest, only a third was covered by about the middle of last century. There was one major tract on high land between the coastal lowlands and the upper Thames (Waihou) and Waikato valleys; and a few outliers on high ground within inland valleys. The Kaingaroa plateau was nearly devoid of forest. Throughout the district there were small patches of forest in the gorges flanking the uplands, in folds of the hills in generally open country, and clumps of swamp forest on the plains. Apart from deep swamps, sand dunes, and the nearly bare summits of Mt. Tarawera, the rest was mainly scrub and fern, with heath and tussock in the south.
This pattern suggests that a nearly universal forest had been reduced by fire, probably by the Polynesians living in middle Waikato valley, along the Bay of Plenty, and about the Rotorua lakes. Fire was their only means of clearing land, but they could not control it. Frequent burning was necessary for a shifting cultivation, to retain fern land for the staple fern root, and to maintain communications. In recorded local traditions large fires are rarely mentioned, but early Europeans commented on them and on the natives' casual attitude towards them.