Dry-Farming

Sun (Auckland), Volume I, Issue 218, 3 December 1927, Page 25 (Supplement)

Dry-F arming

VALUE OF CULTIVATION

Lesson for New Zealanders

IN North America and South Africa hundreds of thousands of previously barren acres have been brought into a state of profitable occupation as a result of the application of dry farming methods. While none of New Zealand’s agricultural districts are handicapped through lack of rain to the same extent as the above-mentioned countries, many of the rules of dry farming could be applied to our farm lands with considerable profit to the occupier.

DRY farming is not a new science, the product of the modern mind. It has been practised since the dawn of civilisation in both Egypt and India. Farmers of the Utah have been raising worthwhile crops for over half a century on dry lands with an annual rainfall of less than 15 inches. Briefly, the term "dry farming,” or “dry land agriculture,” is that particular science or practice which makes possible profitable farming in all districts where the normal average rainfall ranges from little above zero to about 30 inches per annum. It is not farming without moisture, which plainly would be impossible, but it may be defined as the conservation of soil moisture during long periods of dry weather by means of tillage. The principles of dry farming as defined by Dr. Widtsoe, a late director of the State Agricultural College of Logan, Utah, and one of the first to

advocate the reclamation of the deserts by dry farming methods are: Plough deep and in the fall; cultivate the soil in the spring, and as far as possible after every rain; fallow the land every other year in districts with an average rainfall of from 12 to 15 inches, and every third year where the rainfall ranges from 15 to 20 inches; stick to a few staples such as wheat, oats, barley, rye and alfalfa and, when they are established, go on to others. Robbed of its technicalities, dryfarming is simply the cultivation of the soil so as to conserve the moisture. To do this requires constant tilling in maintaining a fine mellow surface soil. It is easy to tell when to cultivate. If the surface soil has a hard, baked appearance, or even a thin crust, cultivation should be done at once, for the moisture is rapidly passing into the air. There are no hard and fast rules for the number of cultivations to be given in a season. Cultivate often enough to keep the soil mellow, weedless and free from crust. This results in four things, storage of rainfall, destroys weeds, admits sunshine and air, and encourages beneficial soil germs. Rolling prior to sowing is also considered an important factor in dryfarming in the fact that it is considered to increase the water holding capacity of light soils, aid the germination of seeds, and crush the lumps in cloddy soils. Crops’ Water Requirements While all farmers are aware of the yast importance moisture is to a growin £> crop, few, perhaps, realise the enormous amount required by the growing crop. Experiments carried out [ n Wisconsin, U.S.A., showed that a two-ton crop of oat-hay required over 1.100 tons of water per acre, equal to

about 9 inches of rainfall. Further experiments in U.S.A. have proved that the average loss of moisture during the summer months through evaporation is equal to over five inches a month. In a 'word, we may think of tho sun and wind as a mighty double-acting force pump continually playing on the surface of the land. Thus, should the top layer of the soil be continually broken up and left loose, as is advocated by dry-soil farmers, there is no one continuous film linking the exposed surface with the subsoil water, and, as surface tension can only lift the water so far as the film is unbroken, that is, as far as the unstirred soil extends, this layer is protected from evaporation by the loose soil above. Thus, when the soil mulch is formed the capillary channels are broken, and the water cannot rise into the loose layer of surface soil. "In the conservation of soil moisture by tillage there is no way of developing

n mulch more effectively,” writes a prominent authority, "than that which is produced by a tool working in the manner of a plough—to completely remove a layer of soil and lay it down again, bottom up, in a loose open condition.” ~ In the humid regions of America it has been found that a mulch three inches deep is sufficient to conserve the moisture of the soil, but in the hot, drier areas twice that depth has been found necessary for the proper protection of the soil moisture. Constant Cultivation Needed The secret of success in dry-farming, as in most other classes of farming, is found in cultivation. Constant cultivation, keeping the fallow ground with a continual mellow surface soil free from weeds and a hard pan, and, afterwards until the height of the crop makes it absolutely impossible, frequent use of the harrows between tho rows. Surely there is a lesson for New Zealand farmers to be got out of the principles of dry-farming. They have been practised with success in Central Otago, but they have a wider application. Desert wastes have been made productive simply by proper cultivation. Does it not give rise to the thought that much more could be done on the fertile lands of this Dominion if greater attention was given to the cultivator and the harrows? Certainly their uso adds considerably to the labour of the farmer, but keeping the soil in propor tilth always pays. This can be seen by the comparison of wellcultivated crops and crops that receive just sufficient attention to ensure them coming above the ground and generally are left to take pot luck afterwards.