60 



Jackson (T.). Control of Cotton Stainers in St. Vincent. — Agric. News, 

 Barbados, xix, no. 483, 3()th October 1920, p. 347. 



In spite of the fact that there are now in St. Vincent no food-plants 

 for cotton-stainers [Dysdercus spp.J to breed on during certain months 

 of the year, there have probably been more stainers present during 

 1920 than in 1919. This is thought to be due in large measure to the 

 use of cotton-seed meal as manure ; when this is not covered sufficiently 

 deep it is possible that numbers of the bugs are able to breed on it for 

 a limited time. A large quantity of cotton was spoilt in the fields 

 on account of heavy rains, and much debris was left lying exposed 

 to insect attack. The area under cotton was also greatly increased 

 from the normal, so that there would naturally be a greater number of 

 insects present. Every effort should be made to destroy as many 

 stainers as possible at the end of every crop before they leave the 

 field. When plants are being destroyed, traps should be laid ; these 

 may be expected to be effective, as it is improbable that the insects 

 would leave an abundant food-supply for less attractive plants. The 

 adequate covering of cotton-seed manure also requires attention. 



Fernald (H. T.) & Bourne (A. I.). Department of Entomology.— 

 ■32nd Ann. Rept. Mass. Agric. Expt. Sta., Amherst, Parts i and ii, 

 1919 (1920), pp. 31a-37a. [Received 18th December 1920.] 



The work in connection with tests of standard insecticides, studies 

 on digger wasps, the onion maggot [Hylemyia antiqua] and codling 

 moth [Cydia pomonella] have been continued as in previous years 

 [R.A.E., A, viii, 75j. The second generation of the codUng moth, if 

 it exists at all, is probably not large enough to need consideration. 

 Observations to ascertain the best time for the second spring spraying 

 for this pest are still in progress. Plathypena scabra, F. (green clover 

 worm) was extremely abundant during 1919, causing serious injury 

 to beans. Its attacks were first noticed in eastern Massachusetts during 

 the latter half of July, and later it was found farther west. Repellent 

 and insecticidal dusts, as well as contact insecticides, have proved 

 useless against this moth, probably partly owing to the habit of the 

 larvae of dropping to the ground when disturbed. A lead arsenate 

 spray applied before the leaves are badly riddled proved a successful 

 remedial measure, but should it be applied when the pods are nearly 

 ready for picking, the beans will require thorough washing before 

 they can be used. Lead arsenate powder also proved successful, but 

 is difticult to apply evenly, and when applied too thickly, it injures the 

 leaves. 



The European corn borer Pyransta nubilalis] has apparently spread 

 beyond its known limits. 



Potato spraying experiments have been continued, various com- 

 mercial brands of lead arsenate, calcium arsenate and magnesium 

 arsenate having been tested in combination with Bordeaux mixture. 

 These three materials appear to be equally good, except as to suspension 

 quality and cost. The results obtained with 4-4-50 Bordeaux mixture 

 combined with powdered calcium arsenate are equal to those obtained 

 with lead arsenate or magnesium arsenate, but the cost is lower. 

 Sulfoleum proved effective against Aphids, but not quite as good as 

 nicotine sulphate. Its chief objection is the injury it causes to foliage. 

 As a cluster-bud spray for apple trees, it was apparently successful 

 against red bugs [Heterocordylus], and did not injure the leaves. 



