Umu and umu tī
Māori had no fireproof cooking vessels, and the umu (earth oven) was an important cooking method, although by no means the only mode of food preparation available. Umu were made by digging a shallow scoop in the ground and building a fire on to which stones were placed. When the fire had died down, meat or vegeta-
[Above] is a view of the outcrops or 'knockers' on the upper part of the quarry complex.
bles wrapped in leaves and sprinkled with water were placed on the hot stones in the scoop, and a layer of earth scraped over the top. The earth layer, excellent insulation, sealed the heat in with the food. Over a period of time, depending on the heat of the fire and the oven stones, and the volume of food, cooking took place; the larger the scoop and fire, the hotter and longer the oven would continue to cook.
Ovens are a very common feature of the archaeological record in the Pacific. In New Zealand sites in the course of excavation, they show as distinctive lenses of heat-reddened and fractured stone with much charcoal; rarely, unopened ovens with the bones of the animal are found. On eroding dunes, the presence of ovens is marked by scatters of fractured and reddened stones. Occasionally ovens show as depressions in the surface of the ground and can be detected in aerial photographs. Commonly, though, ovens show on the ground surface as large blackened areas with an indistinct perimeter only after ploughing and discing. Where fernlands were common the soils are also blackened by a natural process, so the soils can be very black indeed. At the Waitaki River mouth in the South Island, ovens showed particularly clearly in aerial photographs taken about 1960 by Hardwicke Knight. The gravelly or stony soils of the terraces had been ploughed in 1927 and in the following seasons much of the disturbed topsoil blew away, exposing the ovens. At that stage the original recorder, David Teviotdale of the Otago Museum, investigated them. In association with the ovens was abundant evidence of moa bone and Archaic artefacts,
now dated to the thirteenth or fourteenth centuries.
The wider area
Ovens exposed by wind erosion and ploughing on the river terraces at Waitaki River mouth
This area is one of the most important moa-hujitihg sites in New Zealand, dating from the thirteenth century. Carcasses were probably rafted down to a long-lived settlement here. The main river ran past the site immediately to the north, giving access to the site from the sea over a bar, but has since worked its way further north. The ovens show clearly in this photograph taken in about 1960. A crop of wheat or oats had been taken from little-ploughed land, and this photograph was taken after the oven marks had been 'freshened' by discing the crop stubble. The individual circular patches are about 6 m across while the larger area is some 250 by 50 m. The view is to the north.
of the terraces had many other signs of human habitation such as hut floors. Nearer the main river had been the settlement of Māori dispossessed in 1879 of land at Omarama, inland on the Waitaki River.
In 1960, when disced again, the ovens showed clearly as dark patches on the soil surface of Teviotdale's 'No. 1' terrace.
Ti was amongst the tree crops cultivated by the ancestral Polynesians. In New Zealand the native tī (cabbage trees) would have been readily recognised as a potential source of food. The tī roots were prepared for consumption by cooking or steaming in a high-temperature process which converted indigestible starches to fructose (a type of sugar), with a required cooking duration of some 20-40 hours.
The problem of maintaining high temperatures over such a long period was solved by building very large ovens, as much as 8 m across and a metre or more deep, known as umi tī. They are widely recorded in the South Island south o Timaru, and an Otago Peninsula example is shown here.
The need for a starchy or sugary food derived from tī would have been greater in the south, in areas when kūmara could not be grown.