36 ■ Bulletin 332 



1-500 was sprayed on some early varieties of apple trees (Star, etc.)- 

 The fruit buds on these trees were swollen and some were showing 

 the tip ends of very small leaves. Twigs were collected and exam- 

 ined six hours after the spray was applied. The unsprayed twigs 

 showed a 9.5 per cent hatch of all the eggs while the sprayed 

 branches showed 6.3 per cent hatched. Comparing the percentage 

 of hatch of these eggs with those collected near New Bruns- 

 wick, it is evident that the majority of eggs hatched about 48 hours 

 earlier. This is due to the fact that Riverton is approximately 

 50 miles south of New Brunswick. The above twigs were examined 

 again after all the normal eggs had hatched (April 8) and the 

 percentage of hatch in the check was 32 per cent, or an increase 

 of 24.5 per cent, while the sprayed eggs showed 8.9 percent hatched, 

 or an increase of 2.6 per cent. On April 5 the orchard was exam- 

 ined for nymphs and the sprayed trees showed 17 nymphs to 100 

 fruit buds, while the buds of nearby unsprayed trees were in many 

 cases completely covered with aphides. The above orchard experi- 

 ment again shows the value of spraying eggs and nymphs at the 

 hatching period with a combined spray consisting of lime-sulfur 1-9 

 and nicotine 1-500. The proportion of eggs which hatched after 

 they were sprayed in this orchard was about 2 per cent higher than 

 at John Barclay 's orchard. This was probably due to the fact that 

 the material was applied by using long rods and putting the ma- 

 terial on in the form of a mist. Furthermore, an examination of 

 the trees after the spray was applied showed a less thorough job 

 than at Mr. Barclay's orchard. This difference is possibly due to 

 the different types of instruments used in spraying the two or- 

 chards. Other orchards were carefully observed during the delayed 

 dormant spray period and in all cases good results were obtained 

 when the material was applied with extreme care. 



After April 18 the decided value of applying a delayed dor- 

 mant spray of lime-sulfur and nicotine for the control of aphides 

 was not as conclusive this past season as in former seasons, because 

 of the fact that a period of cold stormy weather accompanied by 

 snow and sleet in most parts of the state occurred on April 9 and 

 10, and this weather killed a large percentage of the newly-hatched 

 nymphs. In fact, some unsprayed orchards which had their swollen 

 fruit buds covered with aphides on April 8 did not suffer from 

 aphis attack after the stormy weather was past. During the past 

 season, a large number of adult coccinellid beetles and larvas of 

 syrphid flies also were present in most orchards. 



The time to apply the dormant spray is very important. As a 

 general rule apply the dormant spray as late as possible, for at 

 this time the greatest number of eggs are split and probably some 

 are hatching, especially eggs of A. avence. , The lime-sulfur can be 

 applied with safety as the buds are swellinif (plate 2, fig. B) and 



