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moths are seen to be present in any considerable numbers in cotton 

 fields, the poison should be applied immediately. The moths do not 

 become abundant in the fields, as a rule, until the August generation 

 appears, which is during the last few days of July or the first week of 

 August. As has been stated, poisons should be applied when the eggs 

 begin to hatch in numbers, about the first of August, and not when the 

 laryfe haye attained considerable size, as the}^ haye three weeks later. 

 The first application should be made, as a rule, about the last of Jul}", 

 and should be repeated in about a week or ten days. In case of rain 

 following an application, it should be repeated immediatel}". Some- 

 times a third treatment at a later date is desirable. When the dusting- 

 method is employed, the application should be made early in the morn- 

 ing or after a shower, as the moisture on the plants is imj)ortant to 

 retain the dust as it comes in contact with the foliage and other parts. 



To illustrate the efficiency of poison when applied at the proper 

 time in killing nevvl}'- hatched laryne, the following is of interest: The 

 results were obtained by Mr. C. T. Brues in a small experiment con- 

 ducted at the laboratory at Paris, Tex. On September IT, two plants 

 which were squaring freely were coyered with wire screen cages, one 

 plant haying preyiously been lightly dusted with paris green diluted 

 with dry slaked lime. About 200 hundred eggs which were ready to 

 hatch were placed upon each plant. Obseryations were made each 

 day of the number of fruits injured until October 16, when all 

 of the survi\"ing laryaj had entered the soil to pupate. Only 1 square 

 was injured during this period on the poisoned plant, while on 

 the unpoisoned check plant 31 squares, 2 flowers, 12 small and 2 

 large bolls were destroyed. Notwithstanding the fact that there were 

 heayy rains during the nights of September 20 and 21, the destruction 

 of the laryte b}^ one application was practicall}" complete. In these 

 instances the larya; all hatched practical 1}^ at the same time and shoi'tly 

 after the poison had been applied. Such uniformity in hatching 

 would not be the case in the field, and therefore such complete exter- 

 mination could not be expected. 



As between the dusting and spraying methods of apph'ing poisons, 

 the former seems more practicable. The main objection to the use of 

 a spray is the difficult}^ usually found in securing water in proximit^;^ 

 to fields, and the greater time required in the application of poisons 

 in liquid condition. Geared machinery ma}' be secured for poisoning 

 by either method, but the rather primitiye way so largely used in com- 

 bating the cotton caterpillar, by dusting the poison through bags tied 

 to each end of a pole and carried by a man on horseback, has a decided 

 adyantage on account of cheapness of apparatus. By this means some 

 20 to 25 acres may be poisoned during the few hours suitable for this 

 work in the early morning and late cyening. Where the poison is 



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