Vol. XIII. No. 311. 



THE AGUICULTL'RAL NEWS. 



^<9 



SUGAR INDUSTRY. 



SUGARCANE EXPERIMENTS IN THE 

 LEEWARD ISLANDS, 1912-13. 



The form of thi.> report is virtually the same as that of 

 previous j-ears. The publication is divided into two parts: 

 (1) dealing with varietj- trials and (2) dealing with manurial 

 experiments. The first twelve pages or so of the report 

 include a description in tabular form of the various Barbados, 

 Demerara and Antigua seedlings at present under trial in the 

 Leeward Islands. 



The tables and observations concerning trials with plant 

 canes in Antigua which follow, show that for the year under 

 review the first place in the table of average returns is again 

 occupied by B 4596. The results obtained with B..3922 

 indicate that this variety is worthy of careful attention and 

 trial by planters. Other promising varieties are B.6450 and 

 B.1528. In regard to the experiments with ratoon canes in 

 Antigua. B.3922 occupies the first place in the table and 

 B.156 second. Third on the list is B.4596, a variety which 

 continues to maintain its position as a plant cane and ratoon 

 in a ver_v satisfactory fa-hion. It is observed that the returns 

 during the year under review given by all varietie- are low — 

 a result attributable to the continued dry weather experienced 

 during the preceding seasons, combined with the effects of 

 root disease (Marasmiiis ^acc/iari). 



Turning to the trials with varieties conducted in St. Kitts 

 and Nevis we find that in the mean results for the fifteen 

 varieties grown at all stations as plant canes, the leading 

 place is occupied by B.254. This variety has given an 

 average return of 8,410 lt>. of sucrose per acre and 384 ton.< 

 of cane per acre. This variety has come to the front during 

 the past six years in a rather striking fashion. The second 

 and third varieties on the li^t are B.376 and B.109 re.spect- 

 ively, both of which are now recognized as reliable varieties 

 to grow. It ir interesting to note that the fourth and fifth 

 places are taken by A. 2 and A. 3 respectively— two Antigua 

 varieties which have been grown during the past two seasons 

 at La Gui'rite acd Molineux and at those stations have given 

 satisfactory returns. In the trials with ratoon canes in 

 St. Kitts "during 1912-13 the list is headed by D. 109 with 

 a return of G,170 R. of sucrose per acre, followed by B.4r>96, 

 D.e25 and B.1528. 



In regard to the trials with the varieties in Nevis it 

 would appear that B.254 is a cane which appears to be well 

 suited to conditions in that island. It would seem also that 

 B.3VC, D.109, White Transparent and A.3 are worthy of 

 attention and trial. 



The numerical results which have just been briefly dealt 

 with above are follow ed in the report by a note on the area 

 under cultivation in the different cane varieties in Antigua 

 and St. Kitts. The largest area in Antigua is still occupied 

 by White Transparent, though the total acreage under this 

 cane continues to decrease chiefly in view of its decided 

 susceptibility to root disease particularly on the heavy clay 

 lands of the centre portion of the island. The next largest 

 area in Antigua continues to be occupied by Sealy Seedling 

 which has this year increased its area by 347-i acres. D.147 

 comes next in popularity, closely followed by B.4596. In 

 relation to St. Kitts, the position once again does not evince 

 any very marked change. The area under White Trans- 

 parent shows an increase of 231 acres, while B.20S has 

 decreased its area by 100 acres. The increase in the area 

 under White Transparent is probably the outcome of the 

 introduction of the Central Factory system into St. Kitts, 

 ■whereby varieties giving heavier weights of cane to the acre 



are now preferred to the moderate tonnages and very rich 

 juice characteristic of such varieties as B.208. Although 

 its area has decreased somewhat. B.147 continues to retain 

 the leading position as the standard variety in the northern 

 and northeastern cane-growing area of St. Kitts. 



Part I of the report concludes with some interesting 

 notes on the more important cane varieties already referred 

 to in other connexions above. 



The manurial experiments presented in Part II of the 

 report are conducted with ratoon canes, and the general results 

 of the year under review conform to those obtained in previous 

 seasons, namely, that the principal manurial requirementa- 

 in the Leeward Islands are pen manure for plant canes and 

 a dressing of quick-acting nitrogenous manure for ratoons. 

 In regard to the returns consequent on manuring ratoons, the 

 biggest financial return was got from the plot B which 

 received 40 lb. nitrogen as sulphate of ammonia in one 

 application without potash and phosphate. The profit inci- 

 dental to manuring this plot was 20s. lOd. per acre. (Value 

 of canes assumed as 10s. lO'i. per ton.) It has to be 

 remembered that it is now clearly established that the 

 action of manures in the Leeward Islands is greatly limited, 

 speaking generally, by insufficient rainfall. In St. Kitts 

 where the rainfall was more propitious than in Antigua, 

 distinctly profitable results were obtained from the applica- 

 tion of artificials to ratoons at nearly every station. It may 

 be mentioned here that the reason why quick acting nitro- 

 genous manures improve the growth of ratoons is because 

 of their stimulating action after the shock which the plants 

 sustain subsequent to being cut. The general considerations 

 relating to the manuring of sugar-canes under conditions 

 obtaining in Antigua and St. Kitts are discussed in a very 

 interesting manner towards the close of the report and this 

 section will well repay peru.sal. It is maintained that if 

 it were possible by means of irrigation to counteract 

 the effects of the fluctuations in the level of the water table 

 below the soils in Antigua and St. Kitts, and to obviate 

 the checks to growth thereby engendered, it would seem 

 highly probable that a greater degree of potential produc- 

 tivity would be easily attained. In considering the impor- 

 tance of organic manure it must be remembered that its 

 value lies probably in maintaining that high degree of 

 bacterial activity on which soil fertilit)-, particularly in the 

 Tropics, undoubtedly depends. Soil investigation is the 

 West Indies has fully demonstrated that under favourable 

 conditions the humus contents of tropical soils may be 

 decreased by as much as 25 per cent, in the space of sis 

 months. It is clearly apparent then that the application of 

 organic manures must play an important part in the main- 

 tenance of soil fertility. 



Unfortunately on many estates in the Leeward Islands 

 the conditions are such that it is not always .practicable to 

 produce the requisite quantity of pen manure for application 

 to plant canes, and it is in this direction of endeavouring to 

 find suitable substitutes for, or supplements to, pen manure, 

 in the form of green dressings, naturally occurring 

 material in the shape of weeds, grass and bush, combined 

 with artificial manures, that will receive the special atten- 

 tion of the Agricultural Department for the Leeward 

 Islands during the next few seasons. 



The report concludes with a section dealing with the 

 residual action of fertilizers applied to cane lauds, and 

 molasses as a fertilizer for cane lands. The application of 

 molasses in Antigua has not been productive of beneficial 

 results. It has been urged that molasses is likely to exert 

 a more beneficial action if applied to fields defined to bear 

 plant canes some time before the canes are plante-dl. 



