REPORT ON INJURIOUS INSECTS FOR 1 906. 



EXPERIMENTS WITH INSECTICIDES. 



As stated in my last Report, p. 14, a number of experiments had 

 been made upon the eggs of the Apple Sucker, and in November, 1905, 

 further experiments were commenced with a mixture of 



Caustic Soda (80 per cent) ... ... 2 Ibs. 



boft Soap ... ... ... i lb. 



Water ... ... ... 10 gallons. 



Later, experiments were made with a similar fluid, but double the 

 quantity of soft soap was added. 



Apple twigs, with the eggs of the Apple Sucker and Mussel Scale 

 on, were taken and dipped into these fluids and then allowed to dry. 

 The cut ends were first sealed, and after dipping they were placed 

 under glass, into pots of soil, where they remained until June, 1906. 



Few of the eggs were damaged, and on one twig on which there 

 were sixteen eggs of the Apple Sucker, which was dipped into water 

 twelve hours after being in the caustic soda solution, all the eggs 

 hatched out 



Caustic Soda (98 per cent.) ... ... 2 Ibs. 



Paraffin ... ... ... I pint 



Soft Soap ... ... ... -| lb. 



Water ... ... ... 10 gallons. 



Twigs with the eggs of the Plum Aphis were dipped once into the 

 above fluid. There were sixty-one eggs on the two twigs, and forty- 

 two hatched out. The same fluid was tried warm on other twigs, 

 but the result was the same. 



In a similar fluid, only containing two pints of paraffin, three 

 twigs with eggs of the Plum Aphis on were experimented with, with 

 the following results : 



Out of 1 6 eggs only J hatched out. 



52 30 



103 57 



With three pints of paraffin and the same quantities of soda, 

 soft soap and water as mentioned above, a fluid was made and applied 

 to a large number of twigs. The percentage of eggs killed was 55 per 

 cent. 



When the paraffin was increased to four pints the percentage rose 

 to 70 per cent., and with five pints to 85 per cent., but fell to 66 per 

 ce.nt, when six pints were used, 



