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JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 8 



coast is clear, before descending to the ground to feed. In the same way, when they 

 are suddenly disturbed, they fly back to an adjacent woody plant before going off, 

 or returning to feed. Upon correlating this habit with the majority of infested plants 

 I found that the infestations were not as near the main streets as they were to the 

 alleys back of the lots, and that the feeding places^ — all barns, chicken coops and 

 garbage---were invariably next the alleys. 



The fact that these same feeding places are most often visited by human occupants 

 of the land may be said to somewhat invahdate the theory that the sparrow is 

 chief carrier. In rebuttal note that woody plants in the front yards and near the 

 going and coming of the occcupants of the houses were less often infested. Thus 

 human carriers and their most frequented routes did not usually coincide with the 

 local infestation. This argues for considering birds and not men as the chief cause 

 of infestation in the Wingra Park residence district of Madison. 



Further details support the general conclusion. Of the several hundred city lots 

 in Wingra Park, the tally of feeding places is as foUows: three spots where garbage 

 is openly scattered, but where chickens are not fed; forty-seven chicken coops and 

 twenty-eight barns sheltering horses. The exact number within the general area 

 of sixty-four infested lots is thirty chicken coops, and twenty-three barns, and all 

 but three of these coops and one of the barns failed to have scale infestations within 

 one hundred feet of them. Thus, about 90 per cent of the coops and barns within 

 the infested area had scale located on nearby trees and shrubs, and about 85 per 

 cent of the infested lots had sparrow feeding places on or next to them. 



In some large trees only upper branches were infested, undoubtedly caused by 

 perching birds. Sparrows regularly perch to bask in the sun when not feeding. 

 Many of the infested trees and shrubs were in sunny, sheltered spots where sparrows 

 regularly perch. The fact that twenty-two similar feeding points outside the exact 

 infested area failed to show scale may be attributed to the haijards of chance and 

 to the fact that sparrows fly short distances at any one time. Thus, if scale were 

 on the birds when they retired to their nests, the scales would probably perish over 

 night in hiding on the bird, in crawhng off the bird and in wandering about the nest 

 and eaves. No sparrow nests were noted in the trees, still further reducing the 

 chances of scales to locate on host plants. 



No native wild bird appears to have the exact feeding habits of the Enghsh sparrow, 

 and, therefore, does not seem to fit the actual conditions of infestation as found. 

 I should be glad to hear from other inspectors and entomologists if they differ from 

 the way in which I have tried to apply the actual facts to the theory that Enghsh 

 sparrows are chief carriers of scale in a closely settled residence district. 



A. C. BURRILL, 



Department of Economic Entomology, University of Wisconsin. 



