REPORT OP THE STATE ENTOMOLOGIST 1903 133 



was found that all were killed, while repeated observations up to 

 Sep. 8 failed to reveal any injury to the leaves.. We are, how- 

 ever, inclined to believe that it is more important to make a very 

 thorough application than to use a strong insecticide, and would 

 therefore emphasize the former most strongly. 



Cherry plant louse (Myzus cerasi Fabr.). This common 

 species is likewise generally distributed throughout the State, 

 and always occurs in greater or less numbers on cherrytrees. 

 The past season has been marked by an excessive abundance of 

 this insect, and in some cases sweet cherrytrees have been very 

 seriously injured. We recall, for example, certain trees in Chau- 

 tauqua county, which were so badly infested, that nearly one 

 third of the leaf -bearing portion of twigs had the foliage so badly 

 affected that it curled, died and dropped, and after a time new 

 leaves were developed in their place. This injury was so great 

 that one or two trees died, probably as an indirect result of the 

 severe drain made on their vitality. The presence of these plant 

 lice in large numbers began to be apparent the middle of May 

 and continued through June and even into early July. Keports of 

 injuries were received from a number of counties in widely 

 separated sections of the Sta.te, and were also observed by us in 

 various localities. 



Thorough spraying, as in the case of other species, is the only 

 method of controlling this insect, and when applications are 

 necessary they should be timely so that the insects can not curl 

 leaves and thus obtain shelter from the spray. 



Cabbage aphis (Aphis brassicae Linn.). This species 

 is usually present in small numbers on various cruciferous plants, 

 and only occasionally does it attract much attention on account 

 of its abnormal abundance and consequent injury. Mr J. F. 

 Rose of South Byron states that about the middle of August it 

 was so abundant on early cabbages as to give them a white appear- 

 ance, and Mr George S. Graves of Newport, Herkimer co., reports 

 it as being numerous on turnips in early August. This species 

 was observed by us in very large numbers on rape at Kinderhook 

 the early part of the season. The insects were so abundant as to 



