182 



THE AGRICULTURAL NEWS. 



JuNB 14. 1919. 



COTTON PESTS IN MONTSERRAT. 



The total quan'ity of cotton shipped from Montserrat in 

 the season 191718 was 409,855 lb. From the Report on 

 the Agricultural Department, Montserrat, 1917-18, it appears 

 that the total amount of stained cotton in the crop was 

 27,991 lb., or 68 per cent, of the whole crop. 



There are no data to show what proportion of stained 

 cotton might be expected over the whole island, in the 

 absence of cotton stainer attacks, and provisionally, it is 

 estimated at 3 per cent, of the total reapings. This is due 

 to a variety of causes, including bacterial boll disease, attacks 

 of Nezara bugs, etc. On this basis, reckoning stained cotton 

 at half the value of white cotton, the loss to the island from 

 CO' ton stainer attacks in the past season was in the 

 neighbourhood of £1,280; this makes no allowance for 

 cotton bolls so severely damaged by stainers, that no 

 cotton was reaped from them: the actual loss is, therefore, 

 Tery much in excess of this figure. 



In a few isolated cases the sti.iners appeared early, i e. 

 in the month of June and July, but in most districts they 

 were not numerous until near the close of the year, so that 

 pickings from the eecond crop only in most districts were 

 affected. It is difficult to connect some of the early infested 

 areas with the lecognized host plants of the cotton stainer, 

 viz. the silk cotton and mahoe trees, in the absence of 

 definite observations showing the migratory habits of the 

 insects, and it may be that very considerable distances are 

 traversed by the insects on vacating the host plants referred 

 to. A very small proportion of the silk-cotton trees bore 

 pod« in 1917, and it is only when fruiting that the trees 

 become active agents in the distribution of stainers; more- 

 Over, the number of mahoe trees in the island is quite small, 

 and early infestation of fields has not been found to be 

 necessarily in close proximity to infected host plants. 



Now that the beneficial results obtained in the island of 

 St. Vincent from the total destruction of the host plants of 

 the stainer, viz silk cotton and mahoe trees, are to hand, the 

 inference is that this island would derive similar benefit if 

 like action were taken, and the planting community have 

 expressed the desire that an Ordinance enforcing the destruc- 

 tion of the cotton stainer host plants be put into operation.* 



Observations in 1918 have shown that a very much 

 larger proportion of the silk-cotton trees have fruited this 

 year than usual, and after the dispersal of the cotton from the 

 pod.s. it was the exception to find a tree that had fruited not 

 aaaociated with cotton stainers in the months of May and June, 

 BO that in the current sea.son, the cotton stainer will be more 

 prevalent than usual. At the same time observations also 

 appear definitely to connect certain small malvaceous plants, 

 particularly Sida acuminata, with the tiding over of the 

 •otton stainer from one season to another. This plant 

 is generally distributed, but is found chiefly in the 

 northern and north eastern districts of the island, 

 and is more common on bush lands, or where 

 new clearings have been made. In regard to the very 

 common species of Sida known locally as 'twelve o'clock' 

 (Sida carpinijolia), there is as yet very little evidence that 

 it plays any part in carrying over the stainer from one season 

 to another. 



SLUGS (Veronicel/n occidentalis). 



As reports from cultivators, particularly of provision 

 crops in mountain land.s continue to be received of the 

 depredations of this pest, it may be of interest to record the 

 experience of an epidemic of slugs on the cotton breeding 

 plot in the Experiment Station ia 1917. The previous crop 

 kad been sugar canes, and on the stumps being dug 



*Such an Ordinance haa been pawod Hinee tho above was written. 



out, the trash was ranged into 5-foot rows, the spaces 

 between the rows being tlatforked, and in these 

 spaces the cotton seeds were planted on April 6. Soon after 

 germination it was noticed that the cotton seed leaves wer* 

 being eaten ; slugs were suspected, and their collection was at 

 once undertaken between the hours of 7 and 10 p m. by 

 means of a lamp. On the l.'^th of the month 1,035 slugs 

 were taken, and they were collected in diminishing numbers 

 until the 19th, when only seven were obtained. The 

 weather at this time was very dry, but 60 parts of rain 

 falling on the 22nd, 777 slugs were taken on the same even- 

 ing, and collections were again necessary each evening up to 

 May 8, the largest number, 1,731, being counted on May 1. 

 The area of the cotton plot was J-acre, and between April 13 

 and May 8, after which no further slugs were seen, 8,986 

 were collected and destroyed. 



The manner in which the slugs were distributed during 

 collection indicated that they were emerging from the cane 

 trash as soon as darkness fell, though there was some 

 evidence that they were also coming from the surrounding 

 lawn as well. Whether the collection of the slugs had 

 effectually cleaned up the epidemic or not, it is of interest 

 to record that a neighbouring plot planted in ground nuta 

 on May 31, to which crop the slug is known to be partial, 

 showed no damage from slug injury. 



That the slug is a potential cotton pest there can be no 

 question though this is the first instance, as far as is known, 

 of actual injury in the cotton belt. There are reputed 

 instances of damage occurring near to forest lands. The 

 slugs apparently feed on cotton very slowly, and as many a» 

 three and four have been found adhering to small plants 

 .inly a few inches in height. They eat the leaves, often cut 

 through the young stems, or gnaw away the bark at the side 

 of the young seedling. 



Poison baits are recommended for epidemics of slugs, 

 but very little seems to be known as to reliable means of 

 control, and in the few cases where slugs have appeared in 

 numbers in the Station, collection of the pest seemed the 

 only means of saving the crops. 



It may be mentioned that the cotton plot in th» 

 Experiment Station in 1918 has again been planted after 

 canes, in the same manner as in 1917, and slugs have not- 

 been observed on the plot 



INFANTILE MORTALITY. 



The question df labour supply is one of great impor- 

 tance in all the West Indian colonies from British Ouiana to 

 Jamaica, with perhaps the exception of Barbados. Thia 

 question has been looked at from various standpoints. The 

 reason why the working population of the West Indies 

 instead of increasing should be diminishing deserves serious 

 study. Mr. A. E. CoUens, acting Govern/nent Chemist 

 and Superintendent of Agriculture, Leeward Islands, 

 lately delivered an address at a meeting of the Antigua 

 Agricultural and Commercial Society, which contained 

 matter of considerable interest with regard to this subject. 

 Mr. Collens stated that the question of infantile mortality 

 had been occupying considerable attention in the Weal 

 Indies for very many years, and that he had gone very 

 carefully into it, studying the statistics of Antigua for 

 the past thirteen years, and that in this connexion six 

 points had struck him as being of great importance : — 



(1) The census of 1901 enumerated a population of 

 34,178, while that of 1911 enumerated a population of 

 SI, 394, representing a decrease of 2,784. The populatioa 



