58 



THE GYPSY MOTH. 



In one case in Medford three apple trees which had been 

 sprayed were only saved from defoliation by the use of con- 

 tact insecticides. Two bushels of dead larvae and pupae 

 were gathered from the ground beneath these trees. The 

 injury was most severe wherever a locality had been over- 

 looked in the spring inspection, and numerous eggs thereby 

 allowed to hatch. Early in June a colony of moths was fOund 

 in a small grove of trees in Arlington. Although the trees 

 were sprayed twice with a mixture of Paris green and water 

 (two pounds to one hundred and fifty gallons), the foliage 

 was entirely destroyed, and the caterpillars then spread in all 

 directions through the fields, eating the grass as they went. 

 In spite of all that was done to stay them, many reached the 

 woodland one-eighth of a mile away. Others, having de- 

 foliated the trees, clustered in masses on the trunks and 

 branches and about and upon the rocks beneath. These 

 were finally destroyed by fire. After the larvje upon the 

 trees and undergrowth had been destroyed, the stones 

 beneath the trees were overhauled and pupae were gathered 

 at the rate of about eleven hundred per hour per man. 

 There were similar but less destructive outbreaks in other 

 parts of Arlington, and in Winchester, Chelsea and Melrose, 

 but the one of greatest magnitude occurred in Swampscott. 

 This was beyond the range of the spring inspection, and the 

 colony was found in July by an inspector who had been sent 

 out to search that region for caterpillars. It was situated on 

 a hillside near Humphrey Street. There were several trees 

 infested in a yard and others in a small orchard on a hillside 

 in the rear. Back of the orchard was a pasture somewhat 

 overgrown with trees and shrubs. On the east and extend- 

 ing over the highest point of the hill there was woodland 

 composed of a great variety of trees, both deciduous and 

 coniferous. Beginning at the edge of the orchard a dense 

 undergrowth or jungle of creeping vines and bushes extended 

 into the woodland. 



When this colony was first found the caterpillars had be- 

 gun eating the foliage of nearly all species of trees and 

 plants in the immediate vicinity of the house and outbuild- 

 ings, and were fast spreading into the woodland and pasture. 

 A gang of men was sent to the spot with a spraying tank 



