REPORT OP THE STATE ENTOMOLOGIST 1903 137 



Fruit tree insects 



Plum curculio (Conotrachelus nenuphar Herbst) . 

 This little enemy of stone fruits is prevalent to a greater or 

 less extent in most orchards of this State, and occasionally causes 

 considerable injury. It is remarkable for existing in some locali- 

 ties in such small numbers as to cause practically no damage, 

 while in others a large proportion of the crop would be ruined 

 unless collecting or other repressive measures were employed. 

 Recent experiences by several growers in the State, go far toward 

 showing that thorough and early spraying of the foliage with 

 an arsenical poison affords considerable protection from this pest. 

 This method is preferred by many to the more laborious one of 

 collecting the beetles and is certainly worthy of further trial. 



Diplotaxis liberta Germ. This species is rarely brought to notice 

 on account of its depredations and the same is true of its allies. 

 A complaint was received Sep. 24 through the commissioner of 

 agriculture from Mr John R. Crandall of Hauppauge, who stated 

 that this beetle had stripped all the foliage from many young 

 peachtrees in an orchard of about 30 acres. He added that they 

 worked at night, burying themselves in the dirt under the trees 

 during the day, and that anywhere from 10 to 50 were found 

 under each tree, apparently preferring Elbertas. The beetles oc- 

 curred nowhere except in the peach orchard. This insect is 

 closely related to our common May or June beetles and presum- 

 ably has similar habits, the larvae probably living on grass roots 

 and undoubtedly thriving best in light, sandy soils. Reference 

 to literature shows that another species, D. frondicola 

 Blanch., was recorded in 1871 1 as being very injurious in June 

 to leaves of rose, mountain ash and wild plum in an Iowa nursery. 

 They were about nearly a month, feeding only at night, and were 

 considered one of the worst pests of that year. An attack similar 

 to the one we have recorded occurred in the spring of 1888, 2 at 

 Herndon Va. in a young orchard which had been mostly planted 

 the preceding year. The 12-spotted Diabrotica, Diabrotica 

 12-punctata, was the principal depredator, though a species 



^ridelbaugh. la. State Hort. Soc. Rep't 1871. 1872. p. 161. 

 2 Riley-Howard. Insect Life, 1:59. 



