464 Report S.A.A. Advancement of Science. 



I have seen many farms where the field furrows have been laid 

 out on far too steep a gradient — so steep that an appreciable quantity 

 of soil is being washed away at each irrigation. This, of course, is 

 quite wrong, for it not only carries away some of the best soil, but 

 also cuts up the fields very badly. Then, too, the beds, or acres (as 

 they are sometimes called by the Dutch farmers), are not properly 

 prepared. It is not enough to plough them and turn in the water : 

 they should be carefully levelled, so that the water will spread 

 gradually over the surface. Where the furrows and beds have a 

 gentle slope the water has time to sink into the soil, which it does 

 not do to the same extent when rushing over the ground. One has 

 only to examine the lower edge of the fields to see the waste of water 

 and land that is constantly occurring. 



One of the most important crops in the Transvaal is tobacco, 

 and there again, in my opinion, the system practised is harmful. 

 All the plants are grown in the furrows, and in the early stages the 

 young plants are often entirely submerged during the process of 

 irrigation, and the leaves covered with a deposit of silt, which 

 prevents them from performing their natural functions. Little or 

 no attempt at cultivation or inter-tillage is practised, and naturally 

 the ground becomes hard and baked, thus supplying the conditions 

 favourable to evaporation. I have seen young tobacco seedlings, as 

 tender as water-cress, struggling through the caked surface of a dry 

 furrow. Then they irrigate to soften the ground, and water is 

 applied too frequently. With proper deep irrigation it would be 

 quite unnecessary to irrigate every two or three days, as is the 

 usual practice at present. The young plants undoubtedly require 

 an abundant supply of moisture ; but the larger plants, if well 

 rooted, as -they would be with deep irrigation, ought seldom to 

 require watering more than once in ten or fourteen days. It is a 

 common thing to see the lower leaves attacked by a white mould. 

 On some farms it amounts to from 20 per cent, to 30 per cent, of 

 the leaves, and those that are badly affected can only be used for 

 Kaffir tobacco. One of the best known growers in this Colony 

 agrees with me that the mould is largely due to the system of irriga- 

 tion practised. He also agrees with me that the tobacco plants 

 should be grown between, and not in, the furrows ; but he was 

 afraid it would take more water and more work. I pointed out 

 that by this system fewer irrigations would be necessary, and, conse- 

 quently, less work leading water. T admit it would require more 

 care, but the tobacco planter would be amply repaid by a better crop 

 of leaves. It is the opinion of experts that a lighter and thinner leaf 

 would be grown if the tobacco plants were placed together more 

 closely in the rows ; but this would cause more shade, and some 

 growers are afraid there would be an increase of the white mould. 

 This would probablv be avoided bv a better system of irrigation, 

 but such questions will only be definitelv settled by expert observa- 

 tion on experiment irrigation farms. 



The amount of tobacco of all sorts imported into the Trans- 

 vaal during 1904 was ^202,^']^, and in 1905 it increased to 



