The climate and topography of New Zealand’s sheep farms have led to differences in farm management. There are three main types of land.
The high country has long cold winters and regular snowfalls, which in some years can be heavy and cause high stock losses. Pastures are mostly unimproved tussock and adventive grasses (grasses that are not deliberately planted) such as browntop and sweet vernal. Areas of better soils are cultivated to grow feed crops and improved pastures, often harvested as hay and silage. Irrigation has become widespread for more reliable summer production.
Fine wool from Merino or Halfbred sheep is the main source of income for high-country farmers. Some cross a terminal sire with some of their ewes to produce lambs for the meat trade. Surplus sheep are sold to farmers on rolling hill country and lowlands to breed cross-bred lambs, or for fattening.
Hill country makes up vast areas of pastoral land in the North and South islands. This land is the engine room of New Zealand sheep farming – more sheep and cattle are bred and run there than on any other class of farmland. Before the 1950s, when aerial topdressing and aerial oversowing with grasses and clovers began, hill-country farming was often a marginal enterprise.
North Island hill country has traditionally been dominated by Romneys. In the South Island, the halfbred and Corriedale are found in the drier areas, and the Romney in wetter parts. The hill country can be further subdivided into three classes – easy, medium and hard – according to the steepness of the hills and the length of the growing season.
On hard hill country, farmers run breeding stock. Their income is from wool and the sale of store sheep (sheep to be fattened for slaughter) and cattle to be finished on the easier hills and lowlands. The Perendale was bred to replace Romneys in this type of country.
Medium hill country is used to finish lambs and older sheep for the meat trade, and wool remains an important product.
Easy hill country allows farmers more flexibility in their production choices. Many breed and finish sheep and cattle. In good seasons, farmers on easy hill country also buy in stock for finishing. Cross-breeding to improve productive traits is becoming more common. The easy hills are also the home of stud sheep enterprises, which breed rams for the hard and medium hill country.
The plains, river valleys and easy rolling hills of the North and South islands are the home of intensive sheep farming. In the 2000s, this land has been increasingly given over to dairy farming and horticulture, and in some areas vineyards. Lowland farmers generally finish stock bought off the hill and high country on fodder crops and special pasture mixes. Cattle and sheep studs are also farmed on lowland country.