BETTER DRAINAGE

Wairarapa Times-Age, 7 May 1940, Page 9

BETTER DRAINAGE

INCREASING THE CARRYING CAPACITY. PLANNING NEW WORK. (Issued by Primary Production Council.) Much of the lowlying or poorlydrained areas on many farms is potentially first class land. The institution of a proper drainage system on such areas will allow a considerably increased production in a comparatively short time. Since any means for increasing farm production should be the concern of all farmers, this autumn, winter and spring they should make special efforts to improve, if possible drainage conditions on their farms. The maintenance and improvement of existing drainage systems should be carried out during the ensuing? months. Open drains require cleaning out. Blockages in tile drains may be readily observed and put right during the winter months. Where a new drainage system is seen to be inadequate to carry all water, an extension of the system may be made to cope with the conditions. If new draining work is contemplated, a plan of the field and a survey of levels is necessary. This may best be done after rain when lowlying areas and the natural drainage movement may be seen. On peat soils particular care must be taken in drainage work because too great a lowering of the water table may be disastrous. Open drains can be dug at any time of the year, but are best dug when the soil is easiest to handle. Autumn or early winter usually gives the most opportunity for easy digging as well as being a time when the demand for labour on other farm jobs may not be so great.

For tile drains reasonably moist conditions are desirable so that there is no likelihood of the sides crumbling in during digging operations, and also a clean moulded bottom may be obtained on which to place the tiles. For either tile or open drains, showery weather gives a slight flow of water in the drains which assists in obtaining an even gradient. Mole draining is a cheap and effective method of drainage suited particularly to strong firm clay sojls free from stones with a subsoil of even texture. Mole draining is best carried out when the surface of the ground is firm enough'to hold heavy implements but also when the subsoil is moist and plastic. Thus spring is frequently the most suitable time, but if dry weather is likely to ensue then late spring mole drainage may be rendered useless owing to the opening and cracking of the cuts left by the blade of the plough. It is not possible in a short statement to cover the subject of drainage, but farmers who wish to have a full treatment of the subject of mole draining| may obtain free of cost from the Department of Agriculture, Bulletin No. 170, “Mole Drainage in the Manawatu."