Ngā Tohuwhenua Mai Te Rangi: A New Zealand Archeology in Aerial Photographs
This chapter has been about settlement pattern as it may be detected over large distances or areas. The remaining important source of evidence on settlement pattern on this scale is the vegetation pattern created by fire. In pre-European New Zealand large areas of forested land were burned, including most of the coastal North Island. As with swamps, little sense of the importance of this element of 'landscape management' survives today because of systematic pastoral land clearance in the modern era. However, we can speculate that the firing had a number of purposes: gardening, considered in more detail in chapter 4; increasing the natural supply of early succes-sional plants such as bracken fern, gathered for its rhizome; increasing the availability of some fruits or green leaves of other shrubs of the early succession, edible in their own right but also attracting foraging birds; clearing the landscape of tall vegetation so that enemies could be seen; and finally, making ridgetops easier to walk along.
Burning from natural causes is apparent in New Zealand as far back as the record of pollen in swamps can be read. Human beings started to burn the landscape by the beginning of the thirteenth century, the onset marked by an extensive and massive boost in the amount of tiny fragments of charcoal carried by erosion into swamps. 15 The general pattern of firing would have been up slopes from the source of the fire, and then along ridge tops with the fire travelling for considerable distances where the winds and topography were favourable. Drier, north-facing slopes, suitable for horticulture and adjacent to settlement areas, were repeatedly burned. South-facing slopes remained largely forested, although they too could be burned depending on weather conditions. Slopes generally were only patchily cleared because, before European arrival, trees were not felled before the fire.
The results of modern landscape burning near Ruātoki, inland from Whakatāne
A typical 'Polynesian' burning pattern survives in the landscape today because of the important areas of Maori land within the Urewera Ranges. The pattern results from hundreds of years of firing. The fires start near settlements on the flats, burning up dry faces and then travelling along ridge lines until stopped by the natural topography, the steep slope at the rear of a hill, for example. Fires in the forest canopy may destroy very large podocarps such as rimu over very large areas; this photograph shows no outstanding large trees above the general level of the canopy of tawa, as it would in its natural state. (There has also been selective logging of rimu.) Fern persists in frequently burnt areas, while a forest of rewarewa (on ridges) and tawa develops on less frequently burned country.
The pattern resulting from fire is still maintained today, however the fires are not for gardening but to clear slopes of fern. On the eastern side of the hills near Ruātoki, the pattern is particularly plain. Elsewhere, the planting of pine trees and strict fire control have obliterated these landscapes.
The uses of fire in the European and pre-European period contrasted greatly. In the European period, when maximum areas were required for grazing, the typically Polynesian pattern of patches of open country with a productive mosaic of regenerating shrublands, was not suited to an economic grazing regime. Forest had to be felled, each tree singly, or whole slopes in massive 'drives'. The felled trees were left to dry over a summer, and then burned. This pattern of firing was in many senses more destructive than the Polynesian. It killed wildlife and completely removed its habitat; it led to erosion on a scale similar to that caused by the last eruptions at Taupō. 16
From the point of view of this book, pastoral deforestation left the archaeological evidence of previous human use of the landscape abandoned, out of conte in a sea of grass. Once, human settlements, pā and the small whānau settlements marked by pits and terrace had functioned in broad strips in an intricate relationship with swamps, river courses and relatively small areas of particularly favoured horticultural soils. As people looked out from their settlements, they saw a land of greater or lesser productivity needing to be enhanced by fire—and bounded overall by the mythical vastness of sea and forested hinterland.
A pā in country which is regularly burnt near Ruātoki
The top of the ridge has had fire through it regularly. The platform terraces of the pā are completely covered in fern as a result. The slopes to either side of the pā are reverting to forest, and the natural progress of the fire along the ridge has been halted by the steep drop of the defensive ditch and bank on the far side of the pā.