The Drainage of Grass Land.

Feilding Star, Volume XVI, Issue 54, 29 August 1894, Page 2

The Drainage of Grass Land.

♦ Adapted from " Permanent and Temporary Pastures " by T. Watson. An impression widely prevails that^P however necessary effectual drainage may be for other farm crops, it is of little consequence if grass lands be undrained. This is only one part of the tradition of carelessness which past generations have handed down concerning pastures. No one who is accustomed to examine water-logged grass lands can fail to be impressed by the worthless nature of the herbage they produce. Drainage alone will go a long way towards turning a marsh into a profitable pasture, and without it, careful tillage, costly manures, and the finest grass seeds, will certainly be wasted. The result is only a question of time. Sooner or later the valuable grasses which are sown will be supplanted by sedge and rush, and other semi-aquatic vegetation, until the pasture gradually deteriorates into the worthless state into which undrained land invariably falls. Every •*£ year more water passes through land which is naturally or artificially drained than through soil which is generally saturated with moisture. Where stagnant water lies no rain can enter ; it simply runs off the surface by any outlet it can find. The soil can neither breathe nor digest any fertiliser applied to it, and it is incapable '. of utilising the sun's heat for the developement of plant life. The rain carries into the soil a very large amount of atmosphere, and this is one of the benefits derived from good drainage. The increase in the temperature of the soil, too, is another advantage In the case of water-logged land, the more scorching the sun, the colder the soil becomes immediately beneath the surface. The sun will make the top crust feel warm to the touch, even when full of water ; but force a plunging thermometer through into the. subsoil and it will be found intensely cold. The temperature cannot even be increased ' by ram, for warm water is never known to descend naturally. The rainfall remains on the surface, instead of sinking into the soil and raising the temperature in addition to its many other benefits. An eminent German scientist has demonstrated that there . is an intimate connection between a warm dry soil and economy in feeding cattle. Friable land absorbs more heat than land which is saturated with moisture, and retains the. heat for a longer period. Upon the one animals lie warmer, especially at night, than they do upon the other. Now a large proportion of the food consumed by animals' is utilised for the production of the heat which is constantly dissipated from their bodies. It follows that additional food becomes necessary to replace the animal heat lost by the colder surroundings. Land which is properly drained comes under the influence of another operation of nature, to the great advantage of the crops upon it. ' Water would, after it had passed through the surface to the subsoil, be lost to plant life were it not for the wonderful natural arrangement known as capillarity. As the surface soil becomes freed from water, it draws up and re-absorbs moisture from below ; and it is especially when the soil becomes dry, and its particles are disintegrated, that it possesses this power. The water which is thus brought from the subsoil contains some of the mineral constituents from the formation below, which further aid the growth of plants. This fact accounts for the widely different grasses which are to be seen in old pastures on surface soils that appear identical. The mineral constituents in a state of solution are brought up by the water from considerable depths, and by this means, amongst others, the geological stratum asserts its influence upon the herbage growing on the surface. '