44 Dirpzctok's Kepoet of the 



putting in practice the reform demanded would revolutionize 

 nursery practice — sheer follj without real, precise, abundant 

 evidence of good to be accomplished. The chief defense of the 

 position taken in the circular is that the variations commonly 

 found in trees are fluctuating ones due to environment and are 

 not, unless in very excej)tional cases, transmissible. It must be 

 proved that a character of any particular tree is transmissible 

 before it will be worth while propagating for that character. 



INJUEIOrS INSECTS. 



The efforts of the Entomological Department of the Station 

 have been devoted largely to the defense of the farm and orchard 

 against insect pests. This has involved not only a study of the 

 means of preventing the ravages of well-known insects, but also 

 an investigation of the life history of new forms of insect life 

 with a development of the means of preventing the injuries they 

 would cause. 



The insects of which the life history has been studied during the 

 last five years, in part through laboratory investigation, and in 

 part through field observations, are the following: The poplar 

 and willow borer, leaf-blister mites, the tussock moth, grape-leaf 

 hopper, the fidia or root worm, tree hoppers, the ermine moth and 

 the pear thrips. The important better known insects with which 

 this Department has dealt are the San Jose scale, the cabbage 

 maggot and the pear psylla. 



With the newer insects, the following results have been secured : 

 The studies of the poplar and willow borer resulted in recommend- 

 ing the cutting out and destroying in June of the parts affected 

 with the grubs and, in addition, spraying during July with bor- 

 deaux mixture containing an arsenical poison. 



The ravages of the leaf-blister mite have been general through- 

 out the apple-growing areas of western New York. Experiments 

 demonstrated that the lime-sulphur wash, oil emulsions and 

 miscible oils are efficient remedies for this pest. It is found that 

 orchards regularly sprayed with any of these mixtures are not 



