REPORT OF THE STATE ENTOMOLOGIST 1901 76*3* 



Substances experimented toith. Crude petroleum was tested on 

 a large number of trees, both the Standard and the Titusville 

 oils being used in 20$ and 25$ mechanical emulsions, and the 

 latter was also used undiluted on a few trees. Good's whale oil 

 soap no. 3 in a solution of 1 pound to 4 gallons of water was 

 used with 10$ and 15$ Standard oil, the kerowater sprayer 

 being employed, as last year, in making a mechanical combina- 

 tion between the soap solution and the oil. Good's whale oil 

 soap was also used by itself at the rate of 2 and of 1J pounds 

 to the gallon. 



Time and methods. The apparatus, the hand kerowater spray- 

 ing outfit, was the same as employed last year. The experi- 

 ments were all in the same orchard, for a diagram of which 

 the reader is referred to pi. 3 of the preceding report. It was 

 undesirable to treat all the trees with the substances used on 

 them in 1900; and it will be seen by consulting the diagram, 

 that the different insecticides have been applied to transverse 

 sections of the orchard. This did not always permit of applying 

 the same preparation to several varieties of pears and peaches, 

 but, on the other hand, it was much easier to keep track of 

 different tests. The numbers bestowed on the trees in 1900 

 have been retained, and it is thus very easy to ascertain the 

 previous history of any tree by consulting the preceding report. 



Supplementary notes. There are several observations which, 

 though not strictly a part of the experimental work proper, may 

 as well be recorded in connection with it, since they were noted 

 in the progress of the work. The young of the San Jose' scale 

 were abundant on trees in the experimental orchard July 3, 

 1901, and, as there were a number of young in the black stage, 

 they must have begun to appear about a week before. Sep. 25, 

 young were crawling in considerable numbers on relatively few 

 trees, and the same condition was observed Oct. 15. Thus this 

 period agrees with those observed in preceding years, and 

 the breeding season may be said to extend from the latter part 

 of June through October. 



