. Airplane dusting in the control of malaria mosquitoes. Mosquitoes Control. Airplane Dusting in Control of Malaria Mosquitoes H used was considerably more than enough to cover the field. For the whole cut an estimated mortality of 73 per cent resulted, but with the exception of the one edge practically 100 per cent of the large larvae were destroyed as well as the majority of the small ones. In this connection it may be noted that when mortality of the larvae is not complete those from one-half to full grown are always the first to succumb. The level nature of the rice fields made very favora
. Airplane dusting in the control of malaria mosquitoes. Mosquitoes Control. Airplane Dusting in Control of Malaria Mosquitoes H used was considerably more than enough to cover the field. For the whole cut an estimated mortality of 73 per cent resulted, but with the exception of the one edge practically 100 per cent of the large larvae were destroyed as well as the majority of the small ones. In this connection it may be noted that when mortality of the larvae is not complete those from one-half to full grown are always the first to succumb. The level nature of the rice fields made very favorable conditions for airplane dusting, and the only difficulties in the way of effective treatment appeared to be in the case of fields adjoining the woods or where the hedgerows along the ditch banks were high. Some of the. Fig. -Growth of water chinquapin in Blue Front Lake at the time of the dusting test in 1924 dust was wasted because it remained on the leaves, but when these were dry the mixture did not adhere to them to any great extent. It was found from other experiments that the leaves of the rice plants are very susceptible to burning when a large quantity of Paris green is used, but the quantity necessary to kill Anopheles larvae did not prove destructive to the plants, and in a few small plat tests, where excessive quantities were applied, even severe burning of the leaves did not appear to kill the plants or to prevent normal development of the grain. The summaries of the dusting operations in 1924 are given in Tables 3 and 4, which include the records for the individual Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original King, W. V. (Willard Van Orsdel), b. 1888-; Bradley, G. H. (George Hirst), b. 1893-. Washington, D. C. : U. S. Dept. of Agriculture
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Keywords: ., bookcentury1900, bookdecade1920, bookpublisherwashingtondcusdept
