1926 - Hinds, W. E. The "cloud drift" versus the regular method of dusting. J. Econ. 

 Ent. 19(4):607-608. 



Only the abstract of this paper is published; it describes briefly the method 

 of dusting cotton known as the "cloud drift" as a remedy for the boll weevil. By 

 this method at least, part, of the dust cloud is thrown relatively high in the air 

 above the cotton plant and then drifts slowly across the field, spreading a fairly 

 even distribution of poison over a number of rows beyond those covered directly 

 by the dusting machines. The rate of dust discharged is increased so that the 

 actual amount of poison applied to an acre is practically the same as by the usual 

 methods of application. 



Experiments in Louisiana have shown that the gain of seed cotton to an acre 

 due to regular dusting by the ordinary method was 501 lbs., or 64% over the 

 average untreated yield, while the gain due to the cloud drift method was 599 lbs., 

 or 77%. The "cloud drift" method, however, will be limited in its usefulness by the 

 narrow range of atmospheric conditions within which it can be applied, but when 

 favorable conditions occur and the direction of the drift is across the rows, half 

 the time required for the usual method of dust application can be saved. 



1926 - Howard, L. O. Report (1925-26) of the entomologist. U. S. D. A. Bur. of Ent., 

 30 p. Wash. 



"Against the cotton boll weevil . . . investigations on the attractive prop- 

 erties of certain constituents of the cotton plant have been continued and certain 

 dilutions of trimethylamine and ammonia have also proved attractive in labora- 

 tory tests; the value of these in practical field use is to be determined. While it 

 is expected that several hundred thousand acres of cotton will be dusted by aero- 

 plane, special attention has been given to the development of motor-operated 

 high air-velocity machines for ground dusting." 



1926 - Lyle, Clay. The cotton hopper. Miss. State Plant Bd. Q. B. 6(2):l-4, 1 fig. 



"If the boll weevil is also causing serious damage, a dust of 2 parts super- 

 fine sulfur and 1 part calcium arsenate, 12 lb. to the acre, can be used to control 

 both pests." 



1926 - Marcovitch, S. Supplementary investigations of the fluosilicates as insecticides 

 with observations on the effect of heat and drought on the Mexican bean beetle. 

 Tenn. Agr. Expt. Sta. B. 134, 13 p., 1 fig., 8 ref. Jan. Knoxville. 



Fluosilicates, sodium fluosilicate, and calcium fluosilicate have been pro- 

 duced on a commercial scale. Two brands of the former, known as "light" and 

 "extra-light," are mixed with 15-20% and 25-30%, respectively, of alumnia. The 

 "extra-light" mixture, when undiluted, is sufficiently toxic for many insects, but 

 is not of much value against insects that feed sparingly, such as the boll weevil; 

 itdoes not, however, cause foliage injury to beans, cotton, or cucumbers, although 

 it seriously injures tobacco. 



1926 - Osburn, M. R. Comparative tests with sodium fluosilicate and calcium arsenate 

 for the control of the cotton boll weevil. J. Econ. Ent. 1 9(4):643-644. 



In these tests against the boll weevil, equal field plots of cotton were treated 

 with 5 lbs. an acre of calcium arsenate and with 10 lbs. an acre of sodium fluo- 

 silicate, which is heavier; other plots were left untreated. In cage tests, the 

 sodium fluosilicate apparently acted as a repellent, as well as an insecticide, for 

 weevils tended to collect on the side of the cage after dusting. Actual feeding was 

 not necessary to produce killing, as weevils getting the poison on their feet 

 brushed it off on the mouth parts, and, when placed on poisoned leaves, they died 

 within a few hours without having fed on the leaves. 



Sodium fluosilicate was more effective than calcium arsenate, and became 

 effective in less than half the time. An average control of 80% was attained in 24 

 hours, while 48 hours were necessary for a mortality of 69% with calcium ar- 

 senate. The rapidity of effect is an important factor in rainy weather, as it may 

 obviate the necessity of redusting almost immediately. There was very slight 

 evidence of scorching on the more tender foliage, but not enough to make any 

 attempt to dilute the sodium fluosilicate worthwhile. 



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