58 JOURNAL ,0P ECONOMIC ENTOMOLOGY [Vol. 3 



sprayed with different lime-sulfur solutions. Two subsequent visits 

 were made to the orchard, one before the hatching of the eggs and one 

 after, and we were unable to detect that any good had been done. 



During the past three years we have received several reports from 

 practical fruit growers that attempts to kill the scale by winter appli- 

 cations of lime-sulfur solution have not been successful. However, 

 we also have received reports of success. 



It was, therefore, apparent that an investigation and sprajdng tests 

 were necessary. Accordingly a series of tests was arranged and car- 

 ried out in 1909. The orchard that was selected for the experiments 

 is located at Lo Lo and owned by Mr. Fred Gilbert. It is in sod, 

 composed of old trees, and with a number of varieties. The trees 

 had been cut back and pruned, and as the scale was abundant and 

 fairly evenly distributed, the orchard was quite satisfactory for our 

 purposes. 



In spraying the trees we desired not only to find an insecticide that 

 would kill and be generally satisfactory, but also to discover just how 

 and when the insects or the eggs were killed. We hoped to find an 

 explanation for the apparent lack of uniformity .of results with the 

 use of the lime-sulfur solutions, and remedies for use before the 

 opening of the buds as well as after the hatching of the eggs in June. 

 We therefore conducted a part of our tests on April 17 and 19, before 

 the leaf buds had opened, and then waited for the appearance of the 

 young. Hatching began on June 10, was well under way by June 

 14, and practically completed by June 20. The spraying for the 

 hatched insects was divided into two series, the first being applied 

 in the early part of the hatching period and the second in the latter 

 part, for we desired to know whether the summer treatment, to be 

 successful, should be applied at any particular time during the hatch- 

 ing period. Certain lots of trees were therefore sprayed on June 14 

 to 17, and others on June 21 to 23. 



For convenience the various tests are here tabulated, with the re- 

 sults, as follows : 



I 



First series applied before hatching and before the buds had 

 opened, and intended to kill the insect in the egg stage. Spraying 

 done April 17-19. 



1. Linseed oil emulsion, one gallon to nine of water. 



Raw linseed oil 1 gal. 



Hard soap i^ lb. 



Water to make 10 sal. 



