ECONOMIC ZOOLOGY ENTOMOLOGY. 455 



chief pests of which complaints were received as destroying new fall wheat; 

 and in Nova Scotia they destroyed corn which had grown about 2 ft. in height. 

 Other insects reported upon include root maggots, the woolly apple aphis, the 

 oyster shell, San Jose and terrapin scales, the brown-tail moth, codling moth, 

 eye-spotted bud moth, apple maggot, plum curculio, cankei-worms, Hessian Qy, 

 locusts, the hop flea -beetle, the potato flea beetle (Epitrix cucumeris) , blister 

 beetles, cutworms, the larch sawfly (Nematus erichsonii) , spruce bud-worm 

 {Tortrix fumiferana), bark beetles, the Eastern spruce beetle, bronze birch 

 borer {Agrilus cmxius), ribbed rhagium (Rhagium lineatum), and the birch 

 leaf-mining sawfly (Plilehatrophia mathesoni). Brief notes are also given on 

 insects injurious to garden and greenhouse crops, household insects, mites, and 

 other pests. 



A brief report on the apiary, by D. D. Gray, is appended. 



How to control the pear thrips, S. W. Foster and P. R. Jones ( U, S. Dept. 

 Agr., Bur. Ent. Virc. 131, pp. 24, figs. 15). — This cix'cular is stated to be an 

 abstract of a more comprehensive report to be published on life history and 

 control investigations of the pear thrips conducted since those previously noted 

 (E. S. R., 21, p. 755) were reported. Conservative estimates place the damage 

 caused by this insect in the Santa Clara Valley alone, during the years from 

 1004 to 1910 at nearly $2,000,000, while the loss for the entire State during 

 this period probably exceeds $3,500,000. It is estimated that the thrips in 

 the absence of treatment would cause an average yearly loss to the State 

 of over $1,000,000. 



" On pears the greater injury is produced by the adults, which often prevent 

 the trees from blooming, while on prunes and cherries the larvse frequently 

 prevent a crop of fruit from setting after the trees have come into full bloom. 

 Also, the deposition of eggs into the fruit stems of prunes and cherries so 

 weakens the stems that much of the young fruit falls." 



In recording life history studies, tables are given which show the total 

 daily emergence of thrips from cages, at San Jose, Cal., 1909-10 ; emergence 

 of thrips from cages placed in the ground under trees in pear and prune 

 orchards and from soil samples taken from orchards in November and December 

 and kept in cages in the laboratory, at Walnut Creek, Cal. ; and from cages 

 placed in the ground under trees in orchards and from samples taken from 

 orchards in November and December and kept in cages in the laboratory, at 

 Suisun, Cal. 



In experiments conducted in which various insecticides were tested, it was 

 found that a tobacco extract containing 2| per cent nicotine, diluted at the 

 rate of 1 to 60 in a 6 per cent distillate-oil emulsion, killed all the thrips 

 touched and penetrated well into the pear cluster buds. Directions are given 

 for the preparation of an emulsion, which can be. made at a cost of about 

 5 cts. per gallon for the concentrated article. The commercial results obtained 

 from some of the numerous large scale experiments and demonstrations carried 

 out in pear, prune, and cherry orchards during the season of 1909-10 are 

 reported. While the sprayings necessary to control the thrips are expensive, 

 the outlay of money and labor gives large returns, many experiments in spray- 

 ing showing pet returns of from $100 to $600 per acre more than was secured 

 from adjoining untreated areas. Since the thrips work rapidly and may 

 destroy all prospects of a crop in less than a week's time, the spraying must 

 be done thoroughly and at a time to kill the thrips before the fruit buds have 

 been destroyed. It is recommended that whei-e possible the land be plowed 

 and irrigated in the fall and followed by a thorough spraying in the spring. 



85408°— No. 5—11 5 



