-5- 



9. DDT is safe on peaches v/here standard lead arsenate is not. 



10. DDT, in general, does not cause as much foliage injury to apples as 

 unaafened standard arsenate of lead. 



11. DDT is no more destructive to honeybees than arsenate of lead, probably 

 less. From the evidence at hand, it is not nearly as toxic as origin- 

 ally feared. 



12. DDT v/ill be useful, certainly on quinces, probably on peaches, possibly 

 on apples and to a very limited extent, if at all, on pears. The main 

 factors operating against full-scale use on apples lie in the partial 

 curculio control and the negative red mite control, as v/ell as the 

 doubtful maggot control. 



Control of Oriental Fruit Moth in Elberta Peaches 



Treatanent - --•- — - ^^^^^ 



(1) Sulfur-oil dust (No DDT) 



(2) Sulfur-oil- jDT dust {3fo DDT) 



(3) Sulfur + 5% DDT fused dust (No oil) 



(4) Sulfur + 5% DDT mixed dust (No oil) 



(5) Check - no dust for fruit moth 



Dates of dust applications; July 11-12, August 9. Plot 

 No. 1 received a third dusting on August 30. Remaining plots were 

 not treated on that date. 



CCST O F OP ERATING A^ BULLD OZER 



The following figures were taken from the recor,^,s of a farmer vrho 

 owr.ed and operated a bulldozer which was used 1200 hours in 1943 and 800 hours 

 in 1944, or a total of 2000 hours. 



The bulldozer was purchased in Juno, 1943 at a cost of ^6700. Its 

 estimated life is 10 years or about 10,000 hours, and is given a thorough 

 overhauling annually. 



Total cost of operation over a two year period; 



Fuel, 5000 gallons, Diesel $ 460 



Oil and Grease 300 



Repairs and Parts 120 



Labor for overhauling 180 



Depreciation - 2 years l/S of $6700 1340 

 Interest on investment © 5% (2 years) 



First year - dfo of $6700 « v335 



Second year - bfo of $6030 = $501 636 



Y/'ages of operator 3 $45 per week 1935 



Total cost for U-ro years ^497T 



The total cost of operation (v4971) divided by the number of hours 

 (2000) reveals a cost amounting to approximately $2,50 per hour, 



- - R. H- Barrett 



