june, '17] lovett and robinson: arsenic as an insecticide 347 



Experiment C. — Test of Materials in the Field 



June 8, 1916. Sprayed the foliage of young apple trees in the field; 

 foliage was thoroughly saturated with the different materials. The 

 test was for burning only, as caterpillars were not available in sufficient 

 numbers to warrant a check being made. 



No. 1. AS2O5 at the rate of 1.5 grams to 1000 c.c. H2O, plus lamp black at the rate 



of 2 grams to 300 c.c. H2O. 

 No. 2. AS2O6 at the rate of 1 gram to 1000 c.c. H2O, plus lamp black at the rate of 



1 gram to 300 c.c. H2O. 

 No. 3. AS2O6 at the rate of .75 gram to 1000 C.C..H2O, plus lamp black at the rate 



of 2 grams to 300 c.c. H2O. 

 No. 4. AS2O5 at the rate of 1.5 grams to 1000 c.c. H2O, plus fuller's earth at the rate 



of 2 grams to 300 c.c. H2O. 

 No. 5. AS2O5 at the rate of 1 gram to 1000 c.c. H2O, plus fuller's earth at the rate 



of 1 gram to 300 c.c. H2O. 

 No. 6. AS2O5 at the rate of .75 grams to 1000 c.c. H2O, plus fuller's earth at the 



rate of 2 grams to 300 c.c. H2O. 

 No. 7. AS2O5 at the rate of 1.5 grams to 1000 c.c. H2O. 

 No. 8. AS2O5 at the rate of .75 gram to 1000 c.c. H2O. 



Report on burn; weather throughout fairly cool and cloudy, with 

 showers. 



June 10. Forty-eight hours after applying spray: 



No. 1. Burn general and severe. 



No. 2. Burn general and severe, though probably a little less intense 



than No. 1. 



No. 3. Burn general. 



No. 4. Burn general, though scattered and not particularly severe. 



No. 5. Burn slight. 



No. 6. Burn negligible, only trace. 



No. 7. Burn general, fairly severe. 



No. 8. Burn same appearance and about equal to No. 4. 



Lamp 

 Black 



Series 



Fuller's 



Earth 



Series 



June 11. Three days after spraying: 



Lamp [ No. 1. Burn spreading, very bad. 



Black \ No. 2. Burn spreading, severe. 



Series I No. 3. Burn spreading, severe. 



Fuller's [ No. 4. SHghtly worse than yesterday. 



Earth < No. 5. Same as yesterday. 



Series [ No. 6. Same as yesterday. 



No. 7. Burn increasing. 



No. 8. Burn increasing. 



June 24. Sixteen days after spraying: 



Lamp f No. 1. Foliage burned until about all has dropped. 

 Black < No. 2. Foliage burned until about all has dropped. 

 Series i No. 3. Foliage burned, very bad. 



