IMPERIAL BUREAU OF ENTOMOLOGY. 



REVIEW 



OF 



APPLIED ENTOMOLOGY. 



Series B. ^^^^'^^^^^ 



( ^^^^^24 I9l fr 



Vol. IV.] 



BiSHOPP (F. C.) & Laake (E. W.). U.S. Bur. Entom. A Preliminary 

 Statement Regarding Wool Maggots of Sheep in the United States. 



— Jl. Econ. Entom., Concord, viii, no. 5, October 1915, pp. 466-474. 



The wool maggots, although pests of importance to sheep-owners, 

 have received practically no attention from investigators in the United 

 States. In the Southern States, Phormia regina is active throughout 

 the winter, though it may disappear for a few days during cold periods ; 

 it usually reaches its greatest abundance in the early spring, diminishing 

 as hot weather comes on. In the northern part of the country, this 

 fly is absent during the coldest weather, but is to be fomid in large 

 numbers during the spring and autumn, and in the extreme north is 

 abundant throughout the summer. The adults of P. regina emerge 

 when the temperatures are moderate in autumn and spring. In Texas, 

 infestations occur from the begimiing of lambing, which is about 

 1st December, to shearing time, from April to June. The cessation 

 of injury is due to some extent to the diminution of the numbers of 

 the fly, and especially to the removal of the wool. Lucilia sericata 

 occurs throughout the year in the Southern States, except in the coldest 

 seasons of the winter. It is not so plentiful, however, in late autumn, 

 early spring and in w^arm periods in mid-winter as is P. regina. The 

 adult Lucilia does not appear as early in the spring as that of P. regina. 

 Keproduction does not often take place in winter, even in the extreme 

 South. The adults are present throughout the sununer, though they 

 often diminish in numbers during excessively hot and dry periods. 

 In Texas, the winter is passed in the larval and pupal stages in the 

 soil or beneath carcases. L. sericata has a wide distribution in North 

 America. It is more closely associated with human habitations than 

 P. regina or Chrysomyia macellaria and is seldom seen far from houses. 

 In order to mitigate the injury due to these pests, it is essential that 

 greater care be exercised in destroying the carcases of animals or 

 burying them under at least two feet of earth. Treatment with borax 

 and other chemicals is not as satisfactory as burning. To prevent 

 infestation of the sheep after lambing, this should occur in winter 

 whenever practicable. Strains of hornless sheep should be developed 



(C232) Wt.P. 12/91. 1500. 1.16. B.&F.Ltd. Gp.ll3. 



