S^oL. X. No. 238. 



THE AGRICULTURAL NEWS. 



179 



SUGAR INDUSTRY. 



THE INFLUENCE OF MOLASSES ON 

 SOIL FERTILITY. 



In the last volume of the Ai/rirultmvl A'etvs, p. 339, an 

 article appeared, describing results that have been obtained 

 in Mauritius from the application of molasses to soils in 

 which sugarcane is grown, and in this article it was stated 

 that attention would be given, in a future" number of the 

 Ayricidtaral Nen's, to the work which is being carried out in 

 connexion with this subject at the Station Agronomique, 

 Mauritius. 



In accordance with this, the following facts are taken 

 from the Annual Report of that Station, for 190S. to which 

 reference is made in the article quoted. It is pointed out 

 that the amount of potash contained in molasses and scums, 

 as well as the fact that such a mixture is already a good 

 manure in itself, makes it inexpedient that it should be 

 applied in quantities greater than 1 litre (about 1^ pints) to 

 each hole. It would even seem belter, where there is a short- 

 age in the supply for manurial purposes, to use less than this 

 quantity, in order that the opportunity may be given for the 

 treatment of a larger area of land. Where molasses is used 

 with mixed manure, its relatively high potash content should 

 be allowed for in making the mixtures. Where molasses and 

 scums are used together as a manure, their composition easily 

 explains tlie way in which a largely improved growth of the 

 plants follows their application. It is considered that their 

 employment provides an excellent means of stimulating the 

 growth of backward plants. 



The report goes on to state that, as has been pointed out 

 before, the use of molasses results in an increased growth of 

 the crop whicli cannot be explained from considerations alone 

 of the plant food which is added to the soil in the molasses. 

 The experiments descrilied show that the influence of the 

 molasses is not exhausted during the first crop, but continues 

 to exhibit itself for some time. This influence is seen best 

 in the case of plant canes, and is well shown with ratoons. 

 Where molasses and other manures were used together, 

 the action of the former was found to be strongest in ]ilots 

 which had not received potash, and in those to which no 

 nitrogen had been given; these results are to be expected from 

 the fact of the comparatively high potash content of the 

 molasses and its influence in stimulating the fixation of 

 nitrogen. 



In Mauritius, the molasses is generally applied in the 

 cane holes before planting; but when it is not found possible 

 to do this, it is placed between the rows, either after planting 

 or when the cane has attained a certain amount of growth. 

 The adoption of this .scheme is possible because molasses has 

 not been found to pos.sess any caustic action such as was 

 attributed formerly to it; nor does it damage the plants in 

 any way, provided that it is u.sed carefully and in reasonal.ile 

 quantities. 



The suggestion is made that, on account of the action of 

 molasses in stimulating the nitrogen-fixing organisms in the 

 5-oil, thefe would be sorae advantage in using it after dilution 

 and in small doses at frequent intervals. In relation to this, 

 however, there has to be considered the increased cost of 



the method, and the fact that definite experimentation is 

 necessarj' in order to decide if there is likely to be any gain 

 from its adoption. 



It will be remembered that experiments are being car- 

 ried out in Antigua for the purpose of investigating the 

 influence of molasses on ,soil fertility. The results in these 

 obtained during the second season (1909-10) are now avail- 

 able; they will appear in Pamphlet No. 68 of the Department 

 Series, entitled Jfiuiin-ial. E.rperiments with Siiqar-cane in 

 the Leeward Idandf, 1909-10, which is about to be issued. 

 The experiments continue to .show, as a mean of the two 

 seasons' results, that there is some increase in weight of cane 

 on the plots receiving the molasses. In the second season, 

 however, the effects of the application are not as well marked 

 as in the first : the employment of 200 gallons of molasses to 

 the acre did not increase the yield, while that of 400 gallons 

 gave an additional V'2 tons of cane per acre. 



In regard to the suggestion of residual action of the 

 molasses, mentioned above, a definite experiment was made 

 in Antigua in the latter of the two seasons, in order 

 to decide if this exists. For this purpose, on one of the 

 experiment stations, second ratoons were reaped from plots 

 on which the canes had received molasses as first ratoons 

 only. The results show that there was a decided increase in 

 the' yields of the plots receiving molasses, although as is 

 pointed out, no definite conclusions can be drawn from one 

 experiment. 



In the description of the experiments in Antigua, attSn- 

 tion is drawn to a Bulletin entitled Home Biochemical 

 Investif/ations of Ifairaiinn Soi/s, issued recently from the 

 Experiment Station of the Hawaiian Sugar Planters' Associa- 

 tion. A summary of the conclusions reached as a result of 

 the work, given at the end of the bulletin, shows that 

 molas.ses applied at intervals to growing canes which have 

 received artificial manure is likely to do harm, either by 

 destroying nitrates that have been already applied or by 

 preventing nitrates from being formed from other compounds 

 containing nitrogen, in the manure. Further, it is considered 

 that the application of molasses to fallow land, or to land in 

 which sugar-cane is to be planted after several weeks have 

 elapsed, may have a beneficial efi'ect in stimulating the action 

 of the nitrogen-fixing organisms and thus adding to the 

 store of nitrogen for the crop that will be growing after such 

 a time has elapised as will have allowed this stimulus to have 

 had its proper effect. 



DEPARTMENT NEWS. 



The Imperial Commissioner of Agriculture left 

 Barbados onSaturday, .June -S, 1911, by the S.S.'Guiaua', 

 fur Dominica, on official business having relation to 

 general agricultural matters, and connected with the 

 re-organization of the instruction of agricultural pupils. 

 Dr. Walts is expected to return to Barbados, by the 

 S S. 'Korona', on the 10th instant 



Mr. H. A. Ballon, M.Sc, Entomologist on the Stafif 

 of the Imperial Department of Agriculture, left Barba- 

 dos on May 27 by the 8.S. 'Sobo', for Antigua, for the 

 purpose of making investigations in connexion with the 

 insect pests of sugar-cane in that island. Mr. Ballou 

 will probably return to Barbidos, by the S.S. 'Korona', 

 on .Tune 10. 



