Of the 21 million acres of improved land in New Zealand, only about 1¼ million acres are used each year for the growing of crops. More than two-thirds of these crops provide supplementary feeding on the farm and under 400,000 acres produce crops for sale. Grass and clover seeds for sale are taken from less than 200,000 acres of land used during most of the year for grazing.
The importance of the cropping programme cannot be measured by the relatively small area of land used for it. This programme supplies valuable human foodstuffs and a large pasture-renewal programme is maintained almost entirely on the grass and clover seeds harvested. At the same time a large quantity of these seeds, as well as garden-pea seeds, is available for export. In the recognised arable-farming districts where the life of pastures is limited by climate, cropping is a means of renewing pastures effectively and economically.
Of far greater importance are supplementary feed crops in maintaining stock-carrying capacity at critical times when pasture growth is insufficient. Where rainfall is high and the season for pasture growth is longer it is possible to manage with the use of hay and silage made during times of surplus pasture growth. In the drier and colder areas, however, the necessity for other feed is more evident, and arable farming becomes important. Over half a million acres of crops are grown in Canterbury each year and almost 200,000 acres each in Otago and Southland. In contrast, under 300,000 acres of crops are grown in the whole of the North Island.