THE VALUE OF DRAINS.

New Zealand Graphic, Volume XLIX, Issue 12, 19 March 1913, Page 38

THE VALUE OF DRAINS.

It is reasonable to assume that the dry season is past. As March has come in with rain, it is very improbable that we shall have an extended period of drought after this. A troublesome season is the general verdict on that now passing- better than the previous one in some respects, but far front ideal. But after all. when we examine the matter, it is usually found that the trouble could have been avoided. When an extra abundant rainfall spoils the soil for working purposes for any long period, it is a sure sign that something is wrong! it inav be the soil, but it is far more likely to be want of drainage. When the subsoil is of such a character that the water' is unable to sink readily through it, the water accumulates if there is heavy or continued rainfall until the soil 'becomes full and the air is excluded. In such condition the water disappears very slowly, partly by slow shrinkage and partly by evaporation; the soil gradually becomes more congealed. exclusion of air drives the particles together till they become a solid mass. If they are broken up they get back to the same condition, particularly if plants sire put in so that the soil cannot be well worked. Tn summer time this condition culminates in a shrinkage, resulting in solid masses intersected with cracks. The only effectual remedy is drainage, which will prevent accumulation of water, prevent evaporation to any great extent, and allow air to permeate the soil. The time is now arriving to attend to these matters, which are of

far more importance than is often realised. The making of a drain is a thing easily done wrong. The bottom of a drain should be made as narrow as possible. If pipes are used, they should just fit the bottom; if tools are not available that will enable this to be done. Lower one side of the bottom so that water will run to that side, and Jay the pipes there. But it is useless to lay pipes unless means are taken to lead the water to them. If covered with the soil excavated the water will soon close it up. The pipes may be covered

with scrub manuka tea-tree is as good as anything. The scrub should be laid all one way, the butt ends looking down the drain, being covered with the brush ends of each succeeding bundle. This will leave nothing but the brush visible, and that will prevent the soil from getting among the butts or reaching the pipes. After a time the soil will become more or less set, and it will not clog the drains even when the lighter parts of the scrub have decayed. This kind of drain is not adapted to lawns, for there is sure to be a sinking in for several years. Some imperishable material is preferable for lawns, so that the level will not .be disturbed. In the vicinity of towns, foundry clinkers and ashes are usuallv obtain-

able; they are the best material of all for the purpose. Clean metal or hard rock is also suitable; rotten rock is quite useless, as the gritty particles would be washed in and close the drain. Drains may be, and are, made without pipes at all, using either scrub or clean, hard metal, but obviously the pipes are safest and most permanent. 'Where soil is bad, no opportunity to improve it should be lost. Clay soil may be improved to a very great extent by draining; this alone, by allowing the atmosphere proper play, will effect wonders. Road sand, or any

sand, old manure, ashes from rubbish fires, »are lall good, but .heist of .all materials is turf from an old pasture; this, cut about two inches thick, and stacked till the grass is dead, will improve any soil and add largely to its fertility.