26 



THE AGRICCTLTURAL NEWS. 



January 20. 1912. 



INSECT NOTES. 



INSECT PESTS IN THE WEST INDIES 

 IN 1911. 



Brief accounts of the occurrence of insect pests in 1909 

 and 1910 were given in Vol. IX of the Agricultural J\'ews 

 (see pp. 10 and 410), and it is proposed to present herewith 

 a similar account for the year 1911. 



The information contained in these notes has been 

 obtained by the same means as that presented in the notes 

 for 1910; that is, it has been furnished by the Agricultural 

 OflScers in the Windward and Leeward Islands in res- 

 ponse to a request from the Imperial Commissioner of 

 Agriculture. The reference to the root borer of the sugar- 

 cane in Barbados is the result of personal observation by 

 the Entomologist on the Staff of the Imperial 1 )epartment. 



A Report on the Prevalence of Some Pests and 1 )iseases 

 in the West Indies for the year 1909-10 appeared in the ]Vest 

 Indian Bulletin, Vol. XI, pp. 73-106. This was issued in 

 January 1911, and contained information in regard to pests 

 and diseases for the period from March 1909 to July 1910. 

 A similar report covering the period from July 1910 to the 

 end of December 1911 will appear in a number of the West 

 Indian Bulletin soon to be issued. 



or SUGARCANE. Ihemothhovev {Diatrciea itaic liar alis) 

 was reported as occurring in all the sugar-growing districts, 

 but was not more abundant than usual. 



The weevil borer {Sp/ienopJiorus sericeus) occurred in 

 unusual numbers in St. Kitts, in connexion with an attack of 

 termites. This was on the estate where termites have 

 previously been recorded as attacking .sugar-cane, but not in 

 the same field. It would seem that the fields in which 

 previous attacks occurred have been freed of these pests by 

 the planting of cotton for a few years. 



The root borer of sugar-cane (Diaprepes abhreviatus) 

 occurred again as a pest of sugarcane in Barbados, and 

 caused a con.siderable amount of loss on a few estates, in the 

 crops reaped in the early months of the year. During June 

 and July, the adults were collected in large numbers; they 

 were found hiding among the leaves of canes growing on 

 land where root borer was previously abundant in canes. 

 This method of collection should produce marked results in 

 reducing the numbers of larvae in future attacks. 



At the end of the year (November and December), with 

 the advent of a period of dry weather, the evidences of the 

 presence of the root borer were to be seen in the dead and 

 dying canes in certain fields within the infested area. 



The pink mealy-bug of sugar-cane (Psevdococcvs calceo- 

 lariae) was rather more abundant in Antigua than usual. 

 An unidentified caterpillar, which may prove to be the 

 larva of Thertnesia (ji'iumatalis, caused a small amount of 

 damage by its attacks on the leaves of sugarcane in Antigua; 

 slight attacks of grasshoppers {Schist ocen-a ji<dlens), on young 

 canes, were reported in that island and in St. Kitts. 



OF COTTON. The cotton worm (AhiJiama argillacea) 

 continues to be efficiently controlled in St. Vincent by its 

 natural enemies. This insect has been more abundant in 

 other islands during 1911 than in the two previous years, 

 Montserrat, Antigua, St. Kitts and Nevis having experienced 

 repeated, severe attacks. In the Virgin Islands, as in 

 St. Vincent, natural enemies controlled the cotton worm and 

 no insecticides were necessary. Cotton stainers occurred in 

 about the usual amount towards the end of the crop season 

 in most of the islands. In Montserrat, however, they were 

 more than u.sually abundant in one district, while in St. Kitts 



it is specially noted that these insects were absent from the 

 cotton fields. The black scale of cotton {Saissetia nigra) 

 rarely occurs in abundance in any of the West Indian 

 islands at the present time, as it is efficiently controlled 

 by its parasite Zalophothric mirum. The white Scale {Hemi- 

 chionaspis minor) occurred at the end of the cotton season 

 on old plants, hwi caused no damage. 



The flower-bud maggot {Contarinin g(my2^ii) was re- 

 ported again from Antigua in the early part of "the year, and 

 in November it made its appearance in Montserrat. This is 

 the first authentic record of the occurrence of this pest outside 

 of Antigua. In Montserrat the distribution is general, but the 

 attack, so for, has not been severe. 



The leaf-blister mite {Erioj>l,yes gossypii) did not occur 

 in serious abundance in 1911, generally, but in Montserrat 

 and Nevis it was more prevalent than for several years past. 



In Grenada the green soldier bug {Nexara viridula) oc- 

 curred as a pest of cotton in one district, and a hard-back 

 beetle caused the loss of cotton blossoms on a few plants by 

 eating into the base of the flowers. 



A mealy-bug on the stems of old cotton plants was re- 

 ported toward the end of the year from Montserrat. This 

 insect had not caused any serious damage, and seemed to be 

 well parasitized. 



OF CACAO. Thrips {Heliothrips ruhrocinctus) occurred in 

 Grenada and St. Vincent in sufficient numbers to cause several 

 severe attacks. In St. Lucia and Dominica they were present, 

 but only in small numbers. 



The cacao beetle {Steirastoma depressum) was common 

 in one district in Grenada, but was not reported from any of 

 the other islands. No damage was reported from scale insects, 

 or mealy bug, on cacao during 1911. 



ON LIMES. Scale insects on limes and other citrus crops 

 occurred to about the same extent as in previous years. In 

 Dominica they were rather less al>undant than usual, appar- 

 ently on account of the efficient control, maintained by natural 

 enemies, which was due largely to the very favourable weather 

 conditions which prevailed. In St. Vincent, on the other hand, 

 the natural enemies of scale insects do not exercise a control- 

 ling influence, and the attacks of these pests continue to be 

 troublesome. In St Lucia the rust mite {Phi/toptus olei- 

 vorus) was reported. 



OF RUBBEH. t'astilloa was attacked as usual by mealy- 

 bugs and scale insects. The common mealy-bug (Pseudo- 

 coccus citri) and the Akee fringed scale {Asterolecanium 2>us- 

 tulaiis) are recognized pests of this tree. The habit of Cas- 

 tilloa of shedding its leaves annual!}', and the presence of 

 fungoid parasites of scale insects in the moist localities where 

 this tree is grown, minimise the efl'ect of these pests, gener- 

 ally. Castilloa growing in unfavourable situations is liable 

 to severe attacks. This plant is also annually attacked in 

 Dominica by a white scale, probably Didspis sp. 



OF SWEET POTATOES. This crop was unusually free 

 from attacks of Scarabee {Cry/dorlii/nchus batatae). Sporadic 

 attacks of the sweet potato caterpillar (Protoparce cingu/afa) 

 were reported in Antigua and the Virgin Islands. 



OF GREEN DRESSINGS. Attacks of leaf eating caterpil- 

 lars were experienced in Grenada, St. Vincent, Montserrat 

 and Antigua. These were generally due to the woolly pyrol 

 meth (Thermesia geinmatalis), the larva of which is a well 

 known pest of these crops. In St. Kitts the horse bean 

 (Cunavali'i ensiformis) has been generally adopted by plan- 

 ters for a green dressing crop, as it seems to be less liable to 

 attacks by caterpillars than other dressings, A red spider in 

 Dominica cau.sed some injury to Bengal beans, Jerusalem pea, 

 and to horse bean in its later stages, and pigeon peas were 

 injured by a green fly. 



