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DRY-FARMING CONGRESS, WICHITA, 1914 



subsoil, I would still maintain these were dry-farming methods. And as it 

 is with water-supply, so it is with manuring. When taking part in the 

 discussion that followed the paper I read at the London Rubber Congress, 

 already referred to at the beginning of these notes, Mr. R. W. Lyne 3 Di- 

 rector of Agriculture in Ceylon, called attention to my remark that a de- 

 ficient rainfall discourages the use of manure, and then added, "This ques- 

 tion goes into the province of the new doctrine of farming known as 'dry- 

 f arming'; now one of the points brought out by the Indian Dry-Farming 

 specialists, is that manuring can, to a certain extent, take the place of 

 moisture. The reason of this is, that you get a more concentrated food 

 drawn up into the tree by applying the manure when the rainfall is de- 

 ficient." Nitrate of soda certainly increases the moisture in the soil, by its 

 very nature it would do so; and may I also point out, diverting from the 

 subject for a moment, that, now our supplies of potash are cut off, the use 

 of nitrate of soda has a double benefit on account of the great part that 

 its soda content plays in freeing the potash in the soil and making it avail- 

 able for absorption by the growing crops. Anyone ignorant of this fact 

 has only to study the literature issued by the English Board of Agriculture 

 calling attention to it, whilst supplies of potash from the continent are 

 lacking. 



In Tunis the farmers are stated to be producing olives at a profit with 

 a rainfall of only seven inches, as well as having the Sirocco winds to con- 

 tend with. In spite of these drawbacks they have been so successful that 

 the area under olives in this arid district is being steadily increased year 

 by year, as can be seen in an interesting article on the subject published 

 in "Dun's Review" for May, 1914. In some cases the olives are planted 

 alone, (at times only ten to the acre,) but when interplanted with barley 

 the results are just as satisfactory. Here are found trees (olives) said to 

 be 70 years old, whose roots, it is claimed, cover a larger area than is over- 

 spread by the crown of the tree. This shows, therefore, that the roots ex- 

 tend laterally to a considerable degree. Tunis is said to be ahead of any- 

 thing to be found in the United States even, as regards dust mulching to 

 check evaporation, so maybe this helps the roots to keep moist; but to 

 mulch properly you must keep your roots not only below the surface (and 

 how often are they not projecting to trip you or your horse up as you pass 

 along) but- sufficiently down to let the harrow cut the surface up into the 

 mulch. 



So important a part do the roots play in semi-arid farming that in 

 the San Bernardino desert in California, I understand, abandoned olive 

 trees have lived and grown with an average rainfall of only three inches, 

 but did so on account of the immense area covered by their roots which 

 were found to extend over an area nine times the size of that overspread 

 by the crown or top. All this tends to show how roots will extend in 

 search of water and with all crops even in zones other than these semi- 

 arid ones, I again say, send them down from the very start, first to find the 

 moisture down in the subsoil, secondly to keep the roots and through them 



