136 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 2 



work with the first spraying and to depreciate the value of later spray- 

 ing if the first was properly made. In reviewing the records of previ- 

 ous experiments tile writer has been nnable to find any satisfactory ex- 

 periments to show the value of a single spraying when the eggs are 

 hatching. Our work has been carried on on so large a scale, however^ 

 that there seems to be no doubt of the value of a single spraying at 

 this time. Observations of practical men confirm this. Mr. H. L. 

 Frost advises me that he has frequently observed orchards sprayed for 

 gypsy moth in late June and early July, which showed practically no 

 wormy fruit as a result of this one spraying. The fruit grower should 

 not be encouraged to neglect the more important spraying when the 

 petals drop, but he should know that if for any reason he is unable to 

 spray then that a thorough spraying three or four weeks later will 

 save nearly three fourths of his loss from worminess. 



Several experiments have previously indicated this, but the data 

 was inconclusive. Thus Cordley in 1902- shoAved that where the check 

 tree had 20% wormy, trees given the ' ' 2d, 3d and 4th ' ' sprayings, the 

 first being omitted, had but 5% wormy, while those which had the first 

 spraying also had but 3% wormy. Green and Houser in 1905^ show 

 that in one orchard where 56% of the picked fruit was wormy on un- 

 sprayed trees but 11% was wormy where spraying was given only in 

 July and August, against 5% wormy where six sprayings were given 

 in June, July and August. In another orchard, where 52% of the 

 checks were wormy when picked, but 51^% were wormy in trees 

 sprayed June 22d and July 16th, while those given two previous 

 sprayings had only 3% wormy. These results, however, are conflict- 

 ing and the methods employed were hardly accurate enough to be con- 

 clusive. 



Recently Gossard* found that where unsprayed trees had 46% 

 wormy, spraying when eggs were hatching gave practically 12% 

 wormy, while the first spraying alone gave 6i/o% wormy. Observation 

 has shown that the eggs are laid on all parts of the foliage, that the 

 newly hatched larvas feed on the foliage, and that many enter the 

 calyx by eating directly through the calyx lobes, upon the outside of 

 which a large amount of poison is always lodged. It is evident, there- 

 fore, both from our knowledge of the habits of the insect and from the 

 direct results of experiments, that spraying when the eggs are hatching 

 so as to cover the foliage and fruit is of great value and should not be 

 neglected. 



^Bulletin 69. Ore. Agr. Exp. Sta., p. 150. 

 'Bulletin 160. Ohio Agr. Exp. Sta., pp. 205-208. 

 ^Bulletin 191. Ohio Agr. Exp. Sta., p. 116. 



