Short tussocks (generally less than 50 centimetres tall) mainly grow at lower altitudes. These grasslands are dominated by silver tussock (Poa cita) and hard (fescue) tussock (Festuca novae-zelandiae), often with areas of shrubland or woodland.
In the 1840s, short tussock grasslands made up around 44% of New Zealand’s grasslands. They grew mainly in drier regions – parts of the central and eastern North Island, and particularly the South Island’s plains, interior basins and lower eastern mountain slopes.
These grasslands, which also include areas of the more palatable blue wheatgrass (Elymus solandri), have been greatly modified. They have been grazed, developed for farming, fertilised by aerial topdressing, or sown with imported grasses.
Southern Māori used tussock to make leggings that protected their bare legs from speargrass. They also put tussock in their paraerae (sandals). ‘Patiti (tussock) was a fine thing to put in the paraerae to keep the feet warm and if one was wading it was warmer with patiti round the feet than without it.’ 1
The tall (up to 1.5 metres) tussock grasslands are dominated by Chionochloa – a genus that is largely endemic (found only in New Zealand).
Red and copper tussocks
In the 1840s, red and copper tussock (C. rubra) dominated about 23% of the grasslands.
Today, red tussocks grow on the North Island’s volcanic mountains (mostly on conservation land). In the South Island they occur in smaller areas, and only as far south as North Canterbury. They are found mostly below the treeline, on poorly drained soils that are often peaty and acidic.
Copper tussocks (subspecies cuprea) grew in similar, often extensive, areas further south to Stewart Island, particularly on the Southland plains. These tussocklands are now much reduced – the largest areas were developed for farming.
Snow tussock is the name given to several alpine species of Chionochloa. These occur in grasslands where one species is dominant, or share dominance with other species. Snow tussocks naturally dominate the low alpine zone, about 500 metres above the treeline. They made up around 13% of the grasslands in the 1840s, and have complex distribution patterns.
Two snow tussocks share the alpine zone on the North Island main ranges: broad-leaved (C. flavescens) and mid-ribbed (C. pallens) snow tussocks. These also grow with several others in high rainfall regions near the main divide of the Southern Alps.
Curled snow tussock (C. crassiuscula) is widespread at higher altitudes south of Nelson. It often grows alongside megaherbs (large-leaved flowering plants), with the much smaller snow-patch grass (C. oreophila) in nearby snowbanks. Carpet grass (C. australis) is confined to the north-west of the South Island; four species grow in the south-west. Most of these areas are conservation lands.
Narrow-leaved snow tussock (C. rigida) is found in the south-western South Island, but is more widespread east of the main divide, along with slim snow tussock (C. macra). These two are the most common tussocks on the pastoral grazing lands of the South Island high country. C. rigida occurs mostly below 1,250 metres, south of the Rakaia River. C. macra grows at higher altitudes where C. rigida is present, but is more widespread in the north of the South Island.
After Māori burnt areas of forest and woodland in the drier eastern 'rain shadow' region of the South Island, narrow-leaved and slim snow tussocks extended their ranges below the treeline on the drier eastern side of the mountains. Later, these grasslands were much reduced by pastoral farming (grazing and burning) from the 1850s.