Ngā Tohuwhenua Mai Te Rangi: A New Zealand Archeology in Aerial Photographs
Primarily focused on the cultivation of rootcrops such as kūmara or taro, Māori horticulture survives as only one element of horticultural practice which the first Polynesians attempted to bring to New Zealand. The staple foods in Central Polynesia, derived from tree crops such as breadfruit or coconut, 1 were from trees that could not survive in New Zealand. However, the processing techniques applied to the Polynesian tree crops stayed on in the treatment of New Zealand native counterparts of Polynesian trees, such as the fruiting of karaka (examples of which appear in chapter 13) or the fibres of the epiphytic kiekie. 2 The crops that survived in New Zealand were the plants that were well adapted, through sophisticated cultural practices, to seasonal cold: the root crops, yam, taro and kūmara (sweet potato). 3 Māori had first to seek soil conditions which matched the temperature and physical requirements of their crops, which had evolved and developed in cultivation in the tropics. High mean temperatures, at least over 18°C, over a five-month growing season, were therefore critical. Even where physical conditions were adequate, good or moderate soil fertility was also needed for gardening to be sustained for more than a few years.