'Rew York Agricultural Experiment Station. 449 



twigs. Where the nvmphs are numerous they take so much 

 nourishment from the trees that the new growth is seriously 

 checked. The whole tree assumes a stunted, unhealthy appear- 

 ance. As a natural result the fruit crop is greatly lessened and, 

 in some instances, trees have been killed. The first brood in the 

 spring probably does the most direct injury. A favorite place 

 for the young nymphs is in the axils of the leaves and at the 

 base of the fruit stems. Within two or three days after hatching 

 they cover themselves with honey dew which finally becomes so 

 abundant as to disfigure the leaves and fruits, the amount of in- 

 jury done in this way varying of course w^th the number of 

 ^ nymphs. 



Treatment. — The young nymphs are most easily reached. 

 Close watch for them should be kept when the leaves are unfold- 

 ing in the spring. As soon as the nymphs are found spray the 

 trees thoroughly with kerosene emulsion diluted with about ten 

 parts of water^* or with a solution of whale-oil soap, one pound to 

 from five to seven gallons of water. Two applications about ten 

 days apart will probably be necessary. It is important to begin 

 the work before the nymphs have covered themselves with honey 

 dew as it is then much more difiicult to reach them with a spray. 



SAN JOSE SCALE. 



{Aspidiotus perniciosus Comst.) 



Description^^ — This insect may be briefly described as a small, 

 nearly circular, ash-gray scale with a prominent dark nipple at 

 the center. These are the female scales. They are always 

 greatly in excess of the males and are chiefly responsible for the 

 injury which is done. The San Jose scale attacks the bark, leaves 

 and fruit. In common with certain other scale insects it causes a 



44 Some growers use a much stronger emulsion than this with apparently 

 no injury to the trees. 



46 This insect is discussed more in detail in Bulletin 136 of this Station, 

 pages 587-593, by V. H. Lowe. 



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