The Bulletin, 

 sprayings for oyster- shell scale, 1912 



19 



It will be noticed that the trees used in tests Nos. 2, 5, and 9 received 

 two applications, on March 17th and June 10th (the latter at diluted 

 strength), but in each case the result was not noticeably better than 

 when only the one stronger application was given on March 17th. 



Also, in tests 3 and 6 the trees were treated on June 10th, but not in 

 March. In these tests weaker solutions were used, and the results were 

 "not satisfactory," from which we conclude (in view of the now-estab- 

 lished fact that the eggs hatch mainly in April) that the June treat- 

 ment was too late to give the best results against the young. 



In tests 1 and 2, in both of which the soluble oil was used at 1 gallon 

 to 10 gallons water, in March, the results were "very good," while in 

 tests 8 and 9 in which the lime-sulphur was used at 1 gallon to 8 gallons 

 water, in March, the results are given as "fair." This is our reason for 

 asserting that the oils seem superior to the lime-sulphurs, presumably 

 on account of their greater penetration. 



"Spray-on," which was essentially one of the class of insecticides 

 now generally known as "soluble oils," acted the same when being used, 

 and gave similar results. 



"One-for-all" did not do what might have been expected from its 



comprehensive name. 



******** 



It is freely admitted that these tests do not cover all desirable consid- 

 erations. There was no test of the usual home-made kerosene emulsion, 

 nor of the fire-boiled lime-sulphur, nor does it show entirely satisfactory 

 tests as against the young which hatch in April, for the June treat- 

 ments were not satisfactory, and there were no treatments in late April 

 or early May, which Ave would expect to be the best time to reach the 

 young. 



To offset these possible shortcomings in the tests it may be said that 

 the general action of kerosene emulsion and of fire-boiled lime-sulphur 



•"One-for-All" was a material supposed to combine the good qualities of both the oil and the sul- 

 phur sprays. 



