20 Director's Report of tub 



jurious insects and their natural enemies. A large number of 

 these illustrations have been made during the past summer. 

 They are kept on file for use in bulletins as needed. 



Inspection of misery stock. — Nursery stock inspection has been 

 continued again this season, but to a less extent than the season 

 previous. About fifteen nurseries have been visited, with the 

 result than ten species of insects, all more or less injurious, have 

 been found on young trees about to be shipped, showing that 

 these insects are distributed by means of nursery stock. The 

 species refeiTed to are as follows: The woolly aphis, peach tree 

 boi'er, the pistol-case bearer, oyster-shell bark-louse, scurfy bark- 

 louse, plant lice of various species, the bud moth, the New York 

 plum Lecanium, the oak scale and Aspidiotus ancylus. The San 

 Jos^ scale has also been found in a small nursery in Western 

 New York. Infested stock has possibly been shipped from this 

 nursery for six or eight years past. The present owner is going 

 out of the business and is clearing the land for fruit. 



Experiments in dipping young nursery trees infested with plant 

 lice, — Young nursery trees infested with plant lice cannot be 

 sprayed to advantage, as the lice cause the leaves to curl. The 

 lioe congregate in great numbers on the under sides of the leaves 

 at and near the tips of the young trees. By dipping these in- 

 fested tips the insects may be killed. The object of the experi- 

 ment was to determine the proper strength of the solution (a 

 solution of whale-oil soap) to use. The expense of treating the 

 trees was so slight that no record of it was kept. It was shown 

 that whale-oil soap will kill the lice and may be safely used for 

 this pui"pose at a strength of one ponnd to seven gallons of water, 

 but that a stronger solution, one pound to three gallons, vdll 

 injure the foliage. The weaker solution kills the lice as effectu- 

 ally as the stronger. 



Experiments in spraying young nursery trees. — One-year-old 

 apple grafts were sprayed with green arsenite (Scheele's green) 

 one pound to 100 gallons. The trees were badly infested with 

 the canker-worm. This application was made late in June and 



