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(ii) Pastures Having described the sheep, some reference is necessary to the grasses and clovers which form the pastures on which the sheep graze. The principal pasture constituents are :

(iii) Soils The nature of the soil determines to a large extent which of these grasses a farmer will be able to include in his pastures. It is impossible in a brief outline to give any adequate description of the individual soil types. The main classifications are of recent soils, loams, clays, podzols and skeletal soils. The recent soils are mainly soils deposited by rivers and streams, and are generally very fertile. The loams are good soils, but usually need top-dressing. The clays frequently require much drainage as well as topdressing. The podzols can be either very good or very poor, according to the degree of maturity, while the skeletal soils are mainly poor. But in each main classification there are so many variations that soil can only be judged as a farming factor according to the individual farm or, as Dr. Grange has classified them for us, by their development qualities for farming under Part Three (11, Deterioration) of our report. (iv) Fertility Fertility is a highly-important factor. The chief fertility factor in soil is the quantity of nitrogen available for plant-growth. Raising fertility means increasing plant-growth, and this is achieved by increasing the supply of nitrogen. But nitrogen is rapidly soluble and does not remain available in the soil for long periods. It can be applied as a manure, but, as such, it is very expensive, costing up to £3O a ton. Nitrogen is, however, extracted from the air by clovers and stored in many small nodules on their roots. Thus growing clovers in a pasture is a good way of ensuring a continuous nitrogen supply. Most New Zealand soils, however, are too

Plant. Soil Fertility Nutritive Value. Remarks. Required. Tussock and associated Low .. Low .. Tussock itself not very palatable, but other native grasses grasses associated with it provide feed. Brown-top Low .. Low .. Forms a dense mat, but carrying-capacity low. Satisfactory under suitable conditions. Danthonia Low .. Medium Resists drought well and does not require top-dressing to thrive. Italian rye-grass Short rotation rye-grass High . . A short-rotation grass of first quality. (HI) J Perennial rye-grass .. High .. High .. The best permanent pasture-grass. Needs top-dressing on most soils. Cocksfoot Medium High .. A very useful grass. White clover High .. High .. Needs top-dressing. Subterranean clover .. High .. High .. Needs top-dressing. Does well in dry climates. Lotus major (clover) .. Low .. High .. Does not require top-dressing. Needs a rainfall of 40 in. or more. Montgomery and red Medium High ,. Particularly valuable for development of clovers pumice land.