Edible Products. 



[December, 1908. 



wind. In a nutshell, a judicious use of 

 shade, or trees other than the main 

 crop under cultivation, can in many 

 cases supply the loss of that protection 

 that forest trees extended to cacao and 

 other crops in the wild state. 



In the wild state, however, the ulti- 

 mate aim was by no means to secure 

 the biggest crop, or to reap the largest 

 possible return per acre from the trees, 

 and so long as the trees obtain sufficient 

 moisture they can, under conditions of 

 cultivation, possibly do as well, or better, 

 as regards their output, without the 

 protection of the shade tree, natural or 

 artificial irrigation taking its place. It 

 is worth noting on this point that 

 Trinidad, the cacao producing centre, 

 the most wedded to the use of shade, 

 seems as much or more affected by 

 weather conditions than Grenada, Bahia, 

 or Para, where planters do not look 

 upon the use of shade trees as being so 

 absolute a necessity. To our mind the 

 pros and cons of shade are summed up 

 as follows : — 



Pros. — Fertilization of the soil. 

 Retention of moisture. 

 Prevention of erosion. 

 Discouragement of weeds. 

 Protection from wind. 



Cons.— Encouragement of pest. 



Delay in the maturity of the tree. 

 Reduction of yield. 



According to Dr. Delgado, of Caracas, 

 " the special utility of leguminous trees 

 is emphasized and explained on the 

 ground that, though having superficial 

 roots for the fixation of free nitrogen, 

 they draw nourishment only from the 

 deep strata of the soil, and thus do not 

 come into harmful competition with the 

 coffee." 



" It is interesting to note," adds Mr. 

 O. F, Cook, commenting on Dr. Delgado's 

 " Contrebucion al Estudio del Cafe in 

 Venezuela," "Dr. Delgado's insistance 

 upon the fertilizing value of a stir- 

 ring of the soil, quite outside of 

 tvhat may be necessary in the removal 

 of weeds. The regular use of the Creole 

 plough between the rows of coffee is 

 advised as extremely beneficial, and the 

 injury to the superficial roots is said 

 to be more than compensated for by the 

 efficiency of the new roots put forth 

 in the newly-stirred and aerated soil. 

 Here, again, the possible effect of .stimu- 

 lating the activity of the roots of the 

 leguminous shade tree, as well as the 

 fertilizing value of the detached tuber- 

 cles, are to be taken into account in 

 scientific experiments for determining 

 the lines of rational culture." Those 

 who have discussed the question of 

 disturbing the soil between the cacao 



trees in Grenada with the planters of 

 that Island, will find that they say 

 much the same of cacao as Mr. Cook 

 says of coffee.— Tropical Life, Vol. IV., 

 No. 7, July, 1908. 



MANURIAL EXPERIMENTS WITH 

 CACAO AT DOMINICA. 



The results of the manurial experi- 

 ments with cacao that have now been in 

 progress for many years at Dominica, 

 both at the Botanic Station and in the 

 country districts, are well worthy of 

 study by planters, since they demon- 

 strate beyond a doubt the remunerative 

 returns obtained by judicious applica- 

 tions of manure to cacao plantations. 

 Attention may here be drawn to the 

 most important and interesting features 

 in the results, further particulars of 

 which will be found in a paper by Dr. 

 Francis Watts, c.m.g., that appears in 

 the West Indian Bulletin, Vol. IX., p. 138. 



The manurial experiments at the 

 Station have been carried out on uniform 

 lines since the year 1900, and there are 

 five cacao plots under observation. Of 

 these, one has been regularly manured 

 each year with an application of 4 cwt. 

 of basic phosphate and H cwt. of sul- 

 phate of potash per acre ; a second plot 

 has been annually treated with 4 cwt. of 

 dried blood per acre, and a third has 

 received a complete manure, composed 

 of 4 cwt. of basic phosphate, 1| cwt. of 

 sulphate of potash, and 4 cwt. of dried 

 blood per acre. The fourth plot has 

 been annually mulched with grass and 

 leaves, while the fifth has received no 

 manure whatever. 



The crop returns obtained, which have 

 been recorded since 1902-3, clearly indi- 

 cate the value of manures to cacao 

 plantations. This may easily be seen 

 from a comparison of the returns yielded 

 by the several manured plots during the 

 five years ending 1906-7, with the return 

 given by the unmanured plot. The use 

 of dried blood alone (plot 3), which is 

 primarily a nitrogenous manure, resulted 

 in an increased yield of 187 lb. of dry 

 cured cacao per acre per annum, as com- 

 pared with the unmanured plot. If the 

 dry cacao is valued at the moderate 

 figure of 6d. per lb., the net profit ob- 

 tained as the result of the application of 

 the dried blood, after deducting the cost 

 of the manure, works out at 57s. 6d, 

 per acre. 



The use of phosphate and potash on 

 the first plot has given an increased crop 

 yield which, on the average of the past 

 five years, is equal to 219 lb. of cured 

 cacao per acre per annum over and above 



