PLOUGHING GRASS FOR ROOT & GREEN FORAGE CROPS

New Zealand Journal of Agriculture, Volume 78, Issue 5, 16 May 1949, Page 436

PLOUGHING GRASS FOR ROOT & GREEN FORAGE CROPS

SEASONAL NOTES Contributed by the EXTENSION DIVISION J ATE and tardy preparation of land for root ■ and green forage crops to be sown in spring or early summer is often deplored by agricultural advisers. The time for ploughing and the method of working down are, however, decisions to be made in the light of local study and experience, for it is possible under certain conditions for late ploughing to give better results than early ploughing. ■COR instance, root-growing competitions on the pumice * soils of the central area of the North Island showed that the majority of competitors . securing, good crops ploughed about a month before sowing. Although these soils are light, they hold moisture well and the area has an annual rainfall of about 50in. Pastures on many of the light soils of the Waikato contain redtop in a suppressed state, which, if the land is ploughed in winter, may increase tremendously during wet weather in late winter and early spring, giving a solid mass of twitch which is extremely difficult to work out. If, however, the land is not ploughed until late October or early November, the twitch may be suppressed by cultivation and is not a hindrance to the root or forage crop sown. General advice, then, on the cultivation of land for root and forage crops should be considered in relation to the condition of the particular field. The chief factors to consider are the soil, the rainfall, and whether the land contains twitch or other weeds which may / require particular methods for their suppression. Cultivation of Loams Light soils generally require a shorter fallow than heavy _ soils, and while a month may suffice between ploughing and sowing light, sandy soils < in high-rainfall districts, loams of medium textures generally require a longer fallow. Farmers usually deep plough the land in August, giving at least 2 months for cultivation before sowing. If possible, the grass turf should be hustled, disced, or skimmed before deep ploughing.. Skim ploughing should take place at least 6 weeks before deep ploughing to permit the decay of the turf, which should be thoroughly disced before deep ploughing. The land will

not then require much further preparation before sowing, which could take place within a month. Not much time is lost and frequently time is gained through preliminary working of the surface of the ground. Air is necessary for decay to take place. Hence the difficulty always . experienced wherever top working of the grass turf is not carried out, particularly on soils of heavy texture. Working of Heavy Soils On heavy soils ploughing often cannot be carried out in July, August, and September because of the waterlogged condition of the soil. If ploughing is delayed until spring, there is often insufficient time left for the preparation of the ground, which is itself difficult.' Ploughing should first take -place in autumn or early winter, the skim ploughing when autumn rains have softened the ground and the deep ploughing before winter rains have made it too wet. If the ground is left to lie over the winter, frosts will pulverise the soil and make preparation of the soil in spring easy. In mild climates without the assistance of frosts it will usually be necessary to surface work the land when it is dry enough to. carry implements and tractors or horses, followed by another ploughing before final working down for the seed-bed. The working of heavy land should always be timely. Clay does not break down when it is wet or when it is dry, but in a stage between. If the stage is judged correctly, the work is fairly easy; if not, little progress is made. Frequently it pays on heavy soils to disc ploughed land a few hours after ploughing, even though this upsets the working programme. Early ploughing is therefore an advantage on such soils, as it gives the farmer time to choose periods of working which are suitable for the breaking-down process. Early ploughing also exposes the soil to frost, which makes short work of the large lumps. Heavy soils can be made to grow good root crops, and the failures frequently seen are due mainly to "untimely cultivation.