Vol. IV. Xo. 8S. 



THE AGKICULTUEAL NEWS. 



263 



MANURIAL EXPERIMENTS WITH COTTON 

 IN THE LEEWARD ISLANDS. 



Dr. Francis Watts has turwarded the following 

 report on the nianurial experiments with cotton in the 

 Leeward Islands. As announced in the Afiricultund 

 Kcws O'ol- IlJf. P- 237, July 16, lOOi). uniform 

 experiments were laid out in the islands of Antigua, 

 St. Kitt's, Nevis, and Montserrat : — 



On account of the drought, ov from other causes, some 

 of these exiierinients were not carried to a successful 

 conclusion. Useful return-s have, however, been received 

 relating to twelve series, the mean results of which are 

 given in the table below. 



YIELD OF SEED-COTTON IX POUNDS. 



will be 



The list of experiments to whicli these numbers refer 

 ! found in the AcjncxiUuml Kens, Vol. Ill, p. 237. 



Owing to drought and other detrimental circumstances, 

 the value of the information from the various plots varies. 

 Dealing with the individual plots, perhaps more importance 

 may be attached to the results obtained in St. Kitfs on 

 La Guerite plots I and II, and in ilontserrat on the plots at 

 Dagenham's and White's. At these places the conditions were 

 satisfactory and uniform, and the results were recorded with 

 care. Mr. V. R. Shepherd, who had charge of the 

 La Guerite plots, and Mr. C. Watson, who had charge of the 

 Dagenham's and White's plots, both express the opinion that 

 the manures had but little iuHuence upon the yield of cotton. 



The results of any individual plot are irregular and 

 inconclusive, but on taking the average of all the twelve, it 

 is seen that the irregularities tend to disappear. Satisfac- 

 tory residts in experiments of this kind will only be obtained 

 by taking the average of a large number of experiments. 



Dealing with the mean or average results of the twelve 

 series, the differences are found to be strikingly small. If 

 we assume that differences of 60 Bj. of seed-cotton (equal to 

 about 16 Itj. of lint) per acre are too small to be taken 

 into serious account, we find that only in thirteen cases out 

 of the thirt3--eight do the differences exceed this amount, 

 and of these thirteen, six occur in the salt and sulphate of 

 copper .series, in which instances substances possibly injurioirs 

 to plant life were employed in order to ascertain their effects 

 upon in.sect or fungoid pests; and in these cases it is to be 

 observed that diminished yields have occurred, indicating 

 probably that salt and suljihate of copper both retard growth 

 somewhat. It was not noticed that any particular irnmunit}- 

 from disease was produced by the use of these substances. 

 Xo explanation of the other seven cases of divergence from 

 the average yield can be put forward, and it is not believed 

 that they are related to the manures emplo3-ed. 



From these results we may draw the conclusion that the 

 yield of Sea Island cotton is more influenced by season, by 

 good soil condition and tilth than by artificial manures. At 

 the same time it is well to remember that, while this may 

 now be the case where cotton has been grown for the first 

 time, it by no means follows that this will hold good in the 

 future after cotton has been grown for some years upon the 

 same areas. 



These experiments will be repeated on somewhat similar 

 lines for some little time to come, when it will probably be 

 found that manures play an important part in connexion 

 with soils which have borne a succession of cotton crops. 



An interesting case occurred at Molineux, St. Kitt's, 

 where a series of experiments was laid out. Here the 

 rainfall is usually above the average of that of the Leeward 

 Islands; in the season under review it was 51-5 inches for 

 the six months July to December 1904. In this series the 

 cotton plants grew to a very considerable size but produced 

 so little cotton that it was not practicable to weigh it : the 

 results have not, therefore, been included in the table. This 

 experiment is instructive and seems to point to the fact that 

 cotton will not produce good crops on rich lands subjected to 

 a heavy rainfall although the cotton bushes grow luxuriantly. 



The writer's present views on the manuring of cotton 

 in the Leeward Islands are given in the Agricultural News 

 (Vol. IV, pp. 182 and 198). 



I desire to thank those who have assisted in these 

 experiments, and to express the hope that they will again 

 co-operate in similar experiments to be conducted upon the 

 coming crop. Experiments conducted jointly b3- the Depart- 

 ment of Agriculture and the planters are calculated to secure 

 more confidence and attention than if they were conducted 

 by the Department of Agriculture alone. 



