REPORT OF THE STATE ENTOMOLOGIST I909 I7 



manure or other fly-breeding material can be kept without 

 producing swarms of flies. These measures, while particularly 

 adapted to the farm will also prove of service in villages and 

 cities. 



Brown tail moth 



Euproctis chrysorrhoea Linn. 



This insect, to the consternation of our horticulturists and 

 nurserymen, was brought into New York State by the thou- 

 sands with importations of French seedlings in January 1909. 

 Thanks to the radical measures adopted by the Commissioner 

 of Agriculture on the recommendation of the Entomologist and 

 his associates at Ithaca and Geneva, this pest, so far as can be 

 ascertained, has not become established as a result of this re- 

 cent introduction. The emergency existing in consequence of 

 this wholesale impoirtation made it extremely desirable tO' find 

 some treatment aside from the removal and burning of the 

 winter nests and their inhabitants, which could be relied upon 

 to destroy any caterpillars escaping the inspector's eye. The 

 experiments detailed on following pages show in a striking 

 manner the futility of depending upon any method of fumigation 

 with hydrocyanic acid gas for the purpose of destroying active cat- 

 erpillars, not to mention the more resistant dormant larvae. 



Another infestation. The danger of this voracious leaf eater 

 becoming established in New York was strikingly emphasized 

 June 16 by nursery inspector T. F. Niles of the State Depart- 

 ment of Agriculture finding a small colony of nearly full grown 

 larvae on the estate of W. W. Cook at Port Chester, N. Y. 

 A personal examination by the writer, in company with Messrs 

 Atwood, Niles and other representatives of the Department of 

 Agriculture on Saturday, June 19, resulted in finding aboitt six 

 more full grown larvae, making a total of 16 in all. The in- 

 festation, so far as careful inspection showed at that time, was 

 limited to seven clumps of Crataegus located in the north- 

 west corner of a large cultivated field which had been planted 

 extensively v/ith ornamental shrubs and trees. The caterpillars 

 were tmdoubtedly brought into the State with the Crataegi 

 which had been purchased by Mr Cook from the Arnold Ar- 

 boretum. Subsequent inspections on the 20th and 21st re- 

 sulted in finding no more larvae. It was decided, owing to 

 the dangerous nature of the pest, that drastic measures were 

 by all means advisable. All herbaceous vegetation within 100 



