274 



THE AGKICULTURAL NEWS. 



August 26, 1916. 



In considering the utilization of cotton seed meal 

 for manurial purposes, it is important to realize that 

 this by-product is capable c f being manipulated. When 

 the meal is screened — a process which removes 

 the husk — its value ;is a food and ;vs a manure 

 is obviously increased. Conversely, the addition 

 of this husk to undecorticated meal will produce 

 a mixture of much lower value. If this is done, due 

 allowance should be made in fixing the price, and 

 growers would do well to ask for an analysis of any 

 meal they may purchase or receive. In Barbados, at 

 the time of writing, cotton seed meal is scarce, and 

 the price of meal for feeding purposes is about £'S 

 per ton, while inferior grades for manurial purposes are 

 quoted at £1. Comparative analyses of the two 

 products are not available. 



According to English figures, the estimated value 

 of the manure obtained by the consumption by cattle 

 of 1 ton of cotton seed cake (or meal) undecorticated, 

 is about £8 o^., while that for decorticated is in the 

 neighbourhood of £5 10s. These figures are of 

 interest in that first they show the high manurial 

 value which the meal gives to the animal excreta; and 

 secondly, in that this varies very much according to 

 whether the husk is removed or not. Even greater 

 will be the difference when husk has been added. 



Although these figures seem to refiect very 

 favourably upon the use of cotton seed meal as a feed- 

 ing stutf and indirect fertilizer, it must be remembered 

 that this manurial benefit is seldom realized in 

 practice. Large los.ses accompany the manufacture 

 and storage of pen manure, particularly the liquid . 

 constituents. Unfortunately it is the liquid manure 

 that is richest in available nitrogen, potash and phos- 

 phates; so that to realize a manurial return of £3 to 

 £.5 per ton of cotton seed meal fed to cattle, much more 

 scientific methods must be introduced in coimexion 

 with the storage of pen manure; it is especially impor- 

 tant to make provision for the collection and 

 storage of the drainings that one so fre(|uently sees 

 running to waste. A difficulty presents itself in the 

 tropics, however, in that the cattle are used for working, 

 and are for a considerable period of the day on the roads. 

 Loss to the estate from this cause does not occur in 

 temperate countries. 



As a manure for the soil direct, we have a certain 

 amount of definite information as to the value of 

 cotton seed meal. .When the price is reasonably low, 

 and when there is an adeiiuate supply, planters in 

 Barbados use the meal as a manure for sugar-cane at 



the rate of about i-ton per acre, with apparently 

 satisfactory results. In Dominica, experiments have 

 been in progress foV some years involving the use 

 of the meal as a manure for cacao. The mean result of 

 eight years' trials has been that the cotton seed meal 

 plot has given 1,766 lb. of cured cacao per acre 

 against ],2()4 lb. in the case of the untreated plot. 

 The cost of the application, which was at the rate 

 of 10 cwt. per acre, has been £2 IDs. It is believed 

 that a heavier dressing of cotton seed meal would 

 produce even better results, as the quantity of nitroo-en 

 supplied to the plot in the 600 lb. of meal added, is 

 considerably less than is applied in 4 tons of veo-etable 

 mulch to a plot <jf the same sizd, which gave a mean 

 difterence on the control of -f 792 lb. of cured cacao 

 per acre compared with -|- o02 lb. per acre for the 

 cotton seed meal plot. 



In Nevis some evidence has been obtained which 

 indicates that cotton seed meal is a useful manure 

 for coco-nuts. It is worthy of record, that in the experi- 

 ments now in progress, this manure has come next to 

 a dressing of complete artificials in regard to the 

 benefit produced. But the experiments have not been 

 in progress long enough to accept this as an established 

 fact. In St. Kitts, cotton seed meal has been tried on 

 cotton. No remunerative return has been obtained 

 after many years' trials. This in no way reflects depre- 

 ciatingly upon the general value of the meal as a manure, 

 for in these experiments, even Ithe use of artificial and 

 pen manures has resulted in no appreciable gain, owing 

 to the open and fertile nature of the soil. 



Apart from practical experience, it is safe to 

 argue by analogy, that cotton seed meal must 

 have a very considerable manurial value both 

 in respect of its direct and indirect application 

 to the .soil. Being an organic manure it will 

 have, when applied direct, a beneficial action upon the 

 physical conditions of the soil; it will tend to inci-eiise 

 the humus content and consequently ameliorate the 

 moisture conditions. .So that one is not justified in 

 basing one's judgment of its value upon a mere chemic<xl 

 analj'sis. Nevertheless a ton of cotton seed meal 

 contains about 100 lb. of nitrogen, 24. lb. of potash, and 

 27 lb. of phosphoric acid. It is far richer in nitro-ren 

 than any other organic manure, and is onlv excelled by 

 bat guano and sheep manure in respect of potash and 

 phosphoric acid. Sulphate of ammonia contains 20 per 

 cent.of nitrogen: that is, 1 ton will contain 224 Ib.of nitro- 

 gen. The price of sulphate of ammonia in Barbados at 

 the present time is about £22 per ton. The cost of 1 H). 

 of nitrogen in sulphate of ammonia is therefore approx- 



