THE FARM.

Clutha Leader, Volume XXXIX, Issue 55, 21 February 1913, Page 2

THE FARM.

SUBSOILING AND EXPLOSIVES. In these days of stress and competition in* the cultivation of the soil he who can grow a blade and a-quarter of agricultural produce where one grew before has a distinct advantage over 'he who is satisfied with what unaided Nature provides (states 'Dalgety's Review'). ( Hence, we must utilise the experience of the rest of the world if we mean to compete successfully with it. During the last few years the practice of subsoiiing land by the use of explosives has become fairly general in parts of the United States of America) and very favorable reports have been received regarding the success of this practice. Quite recently experiments in connction with this system nave been conducted on the Botanical Experimental Station at Salisbury ,in Rhodesia. It should here be explained that the object of subsoiiing with explosives is to break up the lower layers of the subsoil, and thus improve the absorptive powers of the soil during the rains, and, further, to so loosen the subsoil that the roots of plants and trees in orchards may more readily penetrate to greater depths. It is claimed that by using explosives at the requisite depths the subsoil will be fissured in all directions, and thus the soil will be aerated and plant food liberated at lower depths than would ordinarily be the case. It* is obvious that by this means deep-rooting plants will be placed under much more favorable circumstances since the roots are enabled to penetrate much more deeply and thus reach stores of plant food which they could not otherwise attaih. Further, by aerating the soil more plant food is liberated and brought up to the surface soil in a capillary rise of moisture. The water-holding capacity of the soil is also greatly increased, and thus all crops are better able to withstand periods of protracted drought. The benefits of deep ploughing and subsoiiing are generally recognised, and the fact that the use of exnlosives loosens til© oil to a greater depth than any plough can reach shows chat the benefits derived from this process should be even more striking. The use of explosives in the manner described below is particularly advocated on land with a heavy, close subsoil, in stony ground, or on soils which tend to form after a few years a hard plough-pan. The latter is frequently the case in orchards and in lucerne fields, where tlio action of irrigating water tends to pack the 'soil immediately below the depths reached by the ordinary shallow cultivator. AVe are indebted to the 'Rhodesia Agricultural Journal' for tlif description of the experiments which follow: A number of holes were drilled in a slightly slanting direction to a depth of three feet, the holes being nine feet apart each way. Virgin soil was treated. The charge consisted of seveneighths gelignite cartridge, which was, of course, connected with a detonator and fuse. In the majority of cases when the explosion occurred nothing more than a slight heaving of the soil was noticed, together with a small puff of dust, round the aperture. In sonic cases, however, where the holes had not been so well drilled a considerable amount of surface soil was slung into the air. In all cases the earth was cracked and fissured in every direction round the hole. On digging out the holes to see the effect a cavity about eight or 12 inches in diameter was noted, from which a number of fissures branched off. It should be noted here that the subsoil of the land experimented upon was of a hard red clay and very impervious to plant roots. The land on which these experiments [ were conducted is now being; ploughed I for the first time, and next season equal-sized plots of various crops will be sown, partly on land thus treated and partly on land which has not been subsoiled in this way. A variety of crops, both deep and shallow rooted, will be tested, and the experiment should prove of extreme interest-and value.

A second series of trials was conducted on a patch of tHree-year-old dry lucerne, which had never given very satisfactory crops. It was thought that the poor cropping power might have been probably due to the hardness of the subsoil and to the fact that the lucerne roots were unable to penetrate sufficiently deep. A check plot untreated on the same stand has been left alongside the treated plot, and it is hoped to treat a further part of the land in the same part just beforo the beginning of the rains. To what extent the use of explosives will become general for ordinary farm crops, where it is practicable, in Rhodesia or elsewhere, depends greatly on the cost of the operation. In the instance mentioned with the Oft apart holes, that-cost amounted to £4 6s 8d per acre, but it is not too much to hope that if the practice became general a cheaper explosive may be obtained,* as is believed to be "the_ case in America.

Should the process be ton expensive for use in the case of ordinary farm crops, there is every reason to believe that ( it will be otherwise in the case of the establishment of orchards of either deciduous or citrous fruits, and should the experiment at Salisbury show a marked improvement with dry land lucerne, when grown on land thus treated, it is by no means improbable that the application of the system to that crop will be profitable also. With a permanent crop which remains on the land for five or 10 years, •mi expenditure of about £o per acre for subsoiling is not excessive, provided of course that sufficiently beneficial results are obtainable.

Since yit date of the llhodesian experiments we have information regarding further ones, which have been nindo in Kent. England, as described in a recent number of 'The, Times.' ! These were for uprooting tree-st.uvns as well as loosening tlie subsoil; the former, however, is not a new process. The charges used for a stump seven or eight feet in diameter consisted of «, central one of 10 wounds and five of one pound <>neh of gelignite fired by electricity. The result was entirely successful, the great mass of wood being thrown clean out of the ground, and broken in a way that, made removal easy. The use of explosives in preparing around _ for tree-planting was proved to the satisfaction of those present. Holes 2ft 9in deep were made with an ordinary crowbar—a process greatly expedited by the use of a simplg leverage invention for removing the crowbar—and a charge of 3oz of Cheddite inserted in each, ignition being effected by an ordinary fuse. Tlie explosion loosented the strong soil, lying on chalk to a depth of 3ft Gin, and to about the same extent jn diameter. It is claira,ed for the"«yet«m that besides saving

labor and expediting the work, it provides a better rooting area for the young trees.' It has boon proved that •fruit trees, planted in this way have taken root more quickly, land 'made more rapid growth than those planted j'in the ordinary manner. The appearance of the ground prepared by explosives certainly suggests such a result. , The cost of the operation was from 4d to 6d per tree, and one man can prepare for 16 trees au hour, i iT,he demonstrations in subsoil-stir-ring were very instructive, and there seems to be considerable possibilities ! for dove lopi ho n't in this direction. The advantages of loosenijiji the land immediately underneath the cultivated strai turn are recognised, but' the operation is often difficult and neglected, because of the danger of bringing to the top the poor subsoil and burying that in which is stored the plant food ac- . cumulated from contiunous manuring and tillage. The heavier mechanical I appliances have done good work, but they have their limitations, especially I in the arid climates of some of our j colonies. In this case 4oz of gelignite j were inserted with holes made with a crowbar 3ft 6in deep at intervals of 10ft. The explosion left little impression on the surface, but the momentary effect was to raise the earth several ' inches above the ordinary level for a distance of from sft to 7ft arpund the ' centre of concussion. When dug the 1 subsoil was seen to be cracked and broken. The cost of the operation is ' estimated at £5 I.os per acre, but it would bo required only once in 10 or ! 12 years -say au average of 10s per acre per annum.

A CURIOUS OCCURRENCE. Tho Tikorangi correspondent of the Tai'anuki 'Daily News' reports a curious occurrence: "In connection with the testing of milk, which is an evergreen topic of conversation among milk suppliers, a peculiar incident has been nbrought under niv notice which, in my opinion, goes to show what a complex and mysterious action the creation of butter-fat really it. Bre fly the facts are as follows One of our well-known settlers who lias retired from dairying is the possessor of a Jersey cow which last seasoiiJie milked for household purposes. Th#m>ik was rich in butter-fat and always showed a good head of cream, so much so that from 71b to 81b of butter was mado weekly, after using what milk was required for the house. This season, so as to obviate the necessity of always coming home to milk, the calf was not entirely weaned, and nas allowed to such a portion, and the rest was milked in the ordinary way. But to the owner's surprise, the milk was so poor that practically no cream at all rose. Tho calf was then/allowed to have its share first, and tho strippings were carefully drawn and set, with entirely the same result, with a test which caine nut at 2.1. 'Hie calf, which was thriving amazingly, was then entirely weaned, and the milk at once resumed its normal character. A thick cream rose, and once again from 71b to 81b of butter per week was made. From the foregoing facts, which can he vouched for, an interesting problem for scientific dairymen arises, and it almost seems as if this cow in particular possesses tho power to control at will the butter-fat contents of her milk. Whether this is so I would not presume to say, but T would be pleased to hear the opinion of more studious and scientific farmers. One thing it does prove is that the variation of the factory test are not always the result of the. alleged nefarious machinations of tho unI Fortunate factory manager." j There are some farmers who believe in castrating their colts as they do their lambs (states "Rusticus" in the 'Lyttelton Times'). The operation is performed while the youngsters are with their dams. It is claimed that a colt doctored thus early in his career is tamer and matures more rapidly than an animal left till he is auyth'ng between a year and two years old. The practice, however, is not likely to become a general one, and it is most inadvisable that it should. A colt castrated when a "sucker" never grows into such a big animal as one that is treated later on. His bones are smaller, as a ride; his whole build is more effeminate and he is weaker. If he is left for one year, or even a couple, he gets a better neck and fore-end, and secures a masculine appearance. Of course, it does not do to leave the animal till it grows into an entire hor.-e, too thick in the neck. The result will I he that the gelding will have th«> '•appearance of a "stag." A colt cut at at two years old unusually makes a good gelding, stylish in appearance, with plenty of spirit. The operation may he safely performed at that age. Very few deaths result if the operator I is up to his work, and is careful and clean in the performance of it.

Novel- give a young * foal castor oil for constipation, is the advice tendered by the- United States Department of Agriculture. A safe and sure corrective is to give, per rectum bv moan-, of n rubber bulb family syringe, a teaspoonful of blood-warm water, to which a teaspoonful of glycerine has been added and well mixed. If relief is not obtainable in half an hour give another injection, and repeat every half-hour until the bowels are evacuated. A dose of castor oil has sometimes caused the death of a promising foal.