CONTROL OF INSECT PESTS McATEE 431 



larvse hatching in forests. He further says that " practically every 

 egg mass laid above the snow line (and over 90 per cent of them are) 

 had been either partially or wholly destroj^ed by birds."-^ Cases of 

 local extermination of tussock moths are recorded for the English 

 sparrows in Massachusetts and the hairy woodpecker in Ohio. 



Even such obnoxiously hairy caterpillars as those of the brown-tail 

 and gypsy moths are eaten by many birds and sometimes to an 

 extent effective in control. Dr. L. O. Howard, chief, United States 

 Bureau of Entomology, states that " Observations extending over a 

 number of years show that birds are important in checking the 

 spread of the brown-tail moth."^" There has been reported to Mr. 

 E. H. Forbush a case in which starlings had locally extirpated a 

 mixed infestation of brown-tail and gypsy larvae, and when Mr. 

 Forbush was in charge of the gypsy-moth campaign for the State 

 of Massachusetts birds were observed to so hold the gypsy moth 

 in check at one locality for several years that work by the State 

 force was suspended. In connection with this early work Dr. E. P. 

 Felt was employed as entomologist, and he found it almost impos- 

 sible to complete certain experiments with larvae protected by net- 

 ting bags because so many caterpillars were taken from the nets by 

 birds. Sixty per cent of the gypsy-moth larvae used in these experi- 

 ments were destroyed by birds. 



The insects of most economic importance in the next family to 

 be taken up — namely, the Lasiocampidae — are the tent caterpillars. 

 These are conspicuous species and many observations have been 

 made of their bird enemies. For the less common species known as 

 the forest tent caterpillar {Malacoso'nia disstria) there are at hand 

 3 records of control and 1 of local extermination, and for the 

 common tent caterpillar {M. mnericana) , G of control and 9 of sup- 

 pression. Entomologists contributing to these records include Misses 

 Mary Treat and Caroline Soule, Prof, Clarence M. Weed, and Dr. 

 John D. Tothill. 



Among the Geometridae or loopers, all smooth caterpillars, readily 

 eaten by most birds, the larvae of the linden-moth {Ennomos sub- 

 sig7iarius) once a pest to shade trees, were so no longer after English 

 sparrows had been introduced and became common. Dr. A. R. 

 Grote and Dr. J. B. Smith cit6 cases of local extermination in New 

 York and New Jersey, and Prof. Glenn W. Herrick says : 



The testimony regarding tiie activity of tlie English sparrow in exterminat- 

 ing this pest in cities seems to show rather conclusively that this much- 

 disliked hird did actually hring about the destruction of this insect. Nearly 

 every writer on the snow-white linden-moth makes acknowledgment to the 



28Proc. Acadian Ent. Soc. 1922, p. 109. 

 »» Farmers' Bull. 264, 1906, p. 18. 



