EFFECTS OF SPRAYS ON APHIS EGGS. 21) 



thought that some requirements should be made to prevent such stock 

 being transmitted. 



Mr. Kirkland stated thai the insect was common in Massachu- 

 setts and some of the nurseries were badly infested. 



Professor Craig called attention to the fact that poplars were unde- 

 sirable shade trees in the East, and raised the question as to whether 

 this insect was not a blessing in disguise if it destroyed them. In 

 the Northwest, where other trees would not grow, they were needed. 

 In the East they should only be used for temporary planting: there- 

 fore it might be better to leave the growing f them to northwestern 

 nurserymen. 



Mr. Burgess remarked that poplars were undesirable shade tree-. 

 and that in East Cleveland, Ohio, where this borer had become estab- 

 lished, and the San Jose and oyster-shell scales seriously attacked 

 them, an ordinance had been passed prohibiting their planting. 



The following paper was presented : 



EFFECTS OF SPRAYS ON APHIS EGGS. 

 By II. E. Hodgkiss, Geneva, N. )'. 



The apple aphides have been unusually abundant for several years 

 in the orchards and nurseries of New York. The species repre- 

 sented are Aphis mali Fab., Siphocoryne avence Fab., and Aj>1t'/s 

 malifolice Fitch. The methods commonly used by our nurserymen in 

 fighting the pests on apple blocks are, either dipping the stocks in oil 

 emulsions or soapy solutions, or the direct application of these sprays 

 to the foliage. In years when these pests are most abundant the treat- 

 ment of the trees in this manner has not been entirely successful 

 owing to belated applications and the protection derived by the in- 

 sects from the curling of the leaves. As eggs on the nursery stock, 

 especially the seedling-, have been numerous, and therefore quite 

 conspicuous, nurserymen have often asked what would be the effects 

 of contact sprays on eggs. As there was abundant opportunity i'ov 

 this work, experiments were conducted during the autumn and winter 

 of 11)04, 1005. and 1906 for the purpose of determining the compara- 

 tive effects of different contact sprays upon aphis eggs. 



For the purpose of the experiment, seedling apple stocks, upon 

 which large numbers of eggs had been deposited, were selected. A.S 

 it was necessary to have tin 4 conditions of the experiment under 

 Control, the trees, upon their removal from the nursery blocks, were 

 grown in a greenhouse. The number of trees under observation was 

 322, and these divided into five lots. All the sprays were tested in 

 each lot. The sprays employed were the sulphur washes, kerosene, 

 kerosene emulsion, whale-oil soap, crude oil, Scalecide. Kil-o-Scale. 



