THE SUPPLEMENT TO THE 



Tropical Agriculturist and Magazine of the G. A. 8. 



Compiled and Edited by A. M. & J. FERGUSON. 



No. 2.] AUGUST, 1912. [Vol. XI. 



EXPLOSIVES IN AGRICULTURE. 



WANTED : TRIALS FOR COCONUT, TEA 

 AND RUBBER PLANNING. 



A great deal has lately been heard about the 

 use of dynamite in agriculture, and some local 

 interest has been aroused in the subject. 



It would appear that " dynamiting " is spec- 

 ially useful in the preparation of land for the 

 cultivation of trees rather than ordinary farm- 

 ing ; and in a country where perennial crops are 

 so extensively grown, it should be profitable 

 to enquire into the possibility of using this 

 novel method of preparing land for planting, 

 particularly where the subsoil is of a hard, 

 impervious description. In the case of hard 

 cabook, or gravel soils, the use of dynamite 

 would seem to be particularly beneficial. A 

 tree planted in a free soil and subsoil has 

 everything in its favour ; but one with an im- 

 pervious stratum below it, is at a great disad- 

 vantage, inasmuch as the progress of the roots 

 is resisted by the hard subsoil. The latter 

 tree will rarely be found to have anything 

 approaching to a tap-root, and has to a great 

 extent to depend upon the comparatively thin 

 upper soil layer for its food-supply, which 

 naturally tends to early exhaustion. 



In many cases the subsoil is rich in the 

 essential elements of plant food ; but as water 

 is the medium by which these are conveyed 

 to the plant, and water cannot penetrate a com- 

 pacted substratum of soil, these underground 

 stores of food are not available. Very often, 

 therefore, it is a case of carrying coals to 

 Newcastle to manure lands of this description : 

 the only treatment necessary being to break up 

 the compacted substratum. 



The method adopted in using dynamite for 

 purposes of "holing" raay 4 be described as fol- 



22 



lows :— A hole 4 to 5 feet deep and about l£Jto 

 2 feet in diameter is made on the exact spot 

 where planting is to be done. At the bottom 

 of this hole is placed che cartridge of suitable 

 dynamite, provided with the usual detonator 

 and fuse. Next the hole is filled with moist 

 earth and beaten down. 



On exploding the cartridge, the surface of 

 the earth will be seen to rise a few inches and 

 subside, and after a few minutes smoke follows 

 from the many cracks in the earth. If now the 

 earth loosened by the explosion is removed with 

 a shovel, it will be found that a pot-hole has 

 formed at the point where the cartridge waa 

 laid, and that innumerable fissures extend far 

 back into the surrounding subsoil. 



It is reported that plants develop much 

 more rapidly after such treatment of the soil 

 than if placed in a spade-dug hole, since not 

 only are the roots enabled to travel with ease, 

 but it is also possible for water to permeate the 

 subsoil and dissolve the plant food buried 

 in it. The most important result of dynamit- 

 ing land would seem to be that a reservoir 

 for moisture is formed underneath, so that the 

 trees planted promise to be drought-resisting. 



An authority, writing on the subject, says 

 that the treatment is beneficial for practi- 

 cally all soils and all types of plants. From 

 this it would appear that there is no reason 

 why dynamite should not prove useful in 

 coconut, tea, cocoa and rubber planting. 

 We understand that ordinary dynamite is 

 unsuitable for agricultural purposes, and that 

 a special kind, not stocked locally, is necessary. 

 We should be indeed surprised if some enter- 

 prising members of the planting community— 

 upcountry as well as lowcountry— do not make 

 the necessary local trials before long. 



