266 



THE AGRICULTUEAL NEWS. 



August 24, 1918. 



INSECT NOTES. 



COTTON STAINER CONTROL IN 

 ST. VINCENT. 



An editorial in the St. Vincent Sinfry for July 2!S, last, 

 comments on a resolution passed by a meeting of the Hoard 

 of Directors of the St. Vincent Electric Light Company, Ltd., 

 in which the Government is urged to adopt the most strin- 

 \ gent measures for enforcing the provisions of the Cotton 

 Staiuers Ordinance and the Cotton Diseases I'revention 

 Ordinance, with respect to the close season and the destruc 

 tion of 'John Bull' and '.Silk Cotton" trees which provide 

 food for the cotton staiuers. Everyone interested iu cfitton 

 growing will approve of this. 



The passing of this resolution by the Klectric Light 

 Company has been made the occasion for reference by the 

 Si'itry to the cotton stainers, and the work of the cotton 

 stainer control, as if this was a new pest, and the work of 

 control had not yet been started; instead of which the 

 cotton .stainer has been known in St. Vincent as a 

 peat of cotton during the entire period of fifteea to 

 sixteen years that Sea Island cotton has been culti- 

 vated as a crop in that i.sland; and the work of .stainer 

 control has been efliciently carried out during the past 

 two cotton seasons. In the earlier days of cotton cultiva- 

 tion in St. Vincent, and, in fact, in all the West Indian 

 islands where cotton stainers occur, the exact nature of the 

 damage done by the.se insects to cotton was not realized. 

 About three years ago it was found that the cotton stainer 

 was closely associated with the internal boll rot, which was 

 the most destructive disease of cotton in St. Vincent. 



In this connexion the work of Mr. Sands, the Agricul- 

 tural Superintendent, Mr. Ilarland, the Assistant Superin- 

 tendent, and Mr. Xowell, the .Mycologist on the Staff of the 

 Imjierial Department of Agriculture, should be referred to. 

 This work has been published in recent numbers of the 

 West Indian Bulktiii and the A^riciilliuul Xai's, and 

 recorded results go to show that the food-plants of the cotton 

 stainer in St. Vincent are now known, and that the destruc- 

 tion of large numbers of 'John Bull' and 'Silk-Cotton' trees 

 has resulted in a very great reduction in the numbers of the 

 cotton stainers. 



As a direct consequence of this work the cotton crop 

 of last season (1017) was much better than that of any 

 recent year. 



The existence of wild trees in the tnountiin.-', to which 

 the cotton stainers resort for food in the absence of those 

 plants which are preferred by the insects, has already had 

 the consideration of the Agricultural Supeiintendent, and 

 references to this aspect of the matter are to be found in the 

 published accounts mentioned above. 



In connexion with the appearance of cotton staini rs in 

 the fields of the present growing crop, the Imperial Commis- 

 sioner of Agriculture has received a letter from the Agricul- 

 tural Superintendent from which the following information 

 is obtained. 



The infestation of certain young cotton fields (May- 

 planted), which were investigated in the Windward and 

 Leeward districts during this month (July), undoubtedly had 

 their origin, not from the forests, but chiefly from the vicin- 

 ity of buildings on lands near to which cotton had been 

 grown. A i'i'x of these insects may have survived on bushes 

 such lis those described in the papers in the West Itidian 

 Bulb tin (Vol XVI, pp. L't5-(i, and Vol. XVII, p. 47). 



< )n one large estate inspected in the AVindward district, 

 in the neighboarhood of buildings used for dealing with si.'ed 

 cotton, there was discovered a very large number of cotton 

 stainers. Kti'orts had been made from time to time, but not 

 systematically or very successfully, to collect the pest since 

 the cotton stalks were cut down in the month of April (3n 

 .luly 11, the Cotlon Inspector reported that the bush near 

 the buildings was' cut and burned, and he had observed that 

 a very large number of stainers were put to tiight. (Jnthe 

 morning of the ne.ict day a heavy infestation of the cotton 

 plants at the Kxperiinent Station and about the buildings of 

 the rjovcrnment 'Jinnery was reported. Xo insects had been 

 observed on the previous day in either of these places. The 

 estate was situated 3 miles to windward of the station, 

 and a liigh easterly wind was blowing on the date mentioned. 

 On the IGtli tlie estate was visited, and very few stainers 

 were to be found; these were being trapped successfully by 

 the methods which had been advised. 



In the Leeward district another case occurred where the 

 pest arrived about tho'l^th or l.'Uh in considerable numbers- 

 this infestation is attributed to the same or a similar source. 



A third case investigated indicated that sufticient care 

 was not exercised in the control of the stainers in the months 

 of May and June in the vicinity of buildings; the pest was 

 rejiorted present at this place during May. 



Close attention has been given to the food-plants of this 

 insect. It may be found necessary to deal with the 'bois-tlot' 

 or 'cork wood' (Odiroina lagoptis). The 'Mountain John 

 Bull' or 'Mahoe Cochon' (Sfcirii/ia cari/xica) is not considered 

 to be sufficiently important at present to make necessary an 

 attempt to eradicate it. 



It is stated that it was not possible to enforce the des- 

 truction of the old cotton stalks by the end of Mircb, last, 

 notwithstanding that the ( 'otton Diseases Prevention Ordi- 

 nance of 1911 was amended on I'ebniary 11, IDl.S, to mike 

 the month of April constitute a close season. On some 

 estates cotton picking was in [irogress at the end of Alarch, 

 and at many places the cotton stalks were not destroyed until 

 .the end of April. Cotton planting was started early in -May, 

 therefore there was no close season. The season was a good 

 one in that there was little dry weather experienced, and the 

 cotton stainer took every advantai;e of the facilities it was 

 offered for tiding over the jicriod from May to July. 



It is only by systematic trap[)ing of the pest in the 

 months of April, .May, and June, and the strict enforcement 

 of the law relating to the close season, that a more effective 

 control of the |)est can be hopud for in the future. If there 

 had been 'Silk-Cotton' and '.lohn P.uH' trees pre.sent this 

 season as formerly, the stainers would have been carried 

 over in enormous numbers, and by this titne the whole indus- 

 try would have been in danger of extinction. The flights of 

 the pest that have been reported so far have been quickly 

 controlled, and the in.sects have not been allowed to breed to 

 any extent. 



The Agricultural Superintendent has spent a great deal 

 fif his time during the past three months in closely studying 

 the pest anil the best methods of trai)ping it, and two other 

 oHicers have devoted a large part of their time in visits to 

 estates and small holdings in connexion with control 



