REPORT OF MR. R. ROBERTSON 333 



SESSIONAL PAPER No. 16 



EXPERIMENTS TO TEST THE VALLE OF BUG DEATH AS COMPARED WITH PARIS GREEN AKD 



BORDEAUX AND PARIS GREEN ON POTATOES. 



Experiments were again conducted to test the comparative value of Bug Death, 

 Paris green and Bordeaux Mixture and Paris green. The plots wero alike in treat- 

 ment of soil, date of planting, &c. The variety. Carman No. 1, was used. The soil 

 was similar on all these plots and was treated in the same way. The plots were each 

 1-33 of an acre. 



On one plot two applications of Bug Death were given, one on July 20 and one 

 August 5. Pour pounds of Bug Death was dusted on the plants at each application. 

 Tho vines were quite large and this amoimt just nicely covered the leaves. It was 

 applied in the early morning when the dew was on. Bugs were jnst commencing to 

 feed at the time of the first application, and very few were noticed at the time of 

 second application. 



Paris Green and water at the rate of 1 oz. to 10 gallons of water, and one quart 

 of lime water added, was applied by means of a spray pump to one plot, July 20 and 

 August 5. At the time of the second application, about as many bugs were present on 

 this plot as on the plot where Bug Death was used. 



Poisoned Bordeaux ]\Iixture, made of 4 lbs. bluestone, 4 lbs. lime, 4 ounces of 

 Paris green and 40 gallons of water, was sprayed on a third plot July 20, August 4 

 and August 26. As many bugs were noticed at the time of the second application as 

 were on the other two plots. No bugs were present at the time of the third application. 



The Bug Death was quite as effective in killing the bugs as either the Paris 

 g'"een or poisoned Bordeaux. No blight was noticeable on any of these plots. The 

 following yields per acre have been calculated from the weight of tubers taken from 

 each of these plots of 1-33 of an acre : — 



How treated. Yield per acre. 



Bush. Lbs. 



Bordeaux and Paris green 350 24 



Bug Death 340 16 



Paris green 319 



MATERIALS USED AND COST PER ACRE. 



Biio Death Plot. 



1st application, 132 lbs. per acre, at Tc. per lb $ 9 24 



2nd application, 132 lbs. per acre, at 7c. per lb 9 24 



$18 48 

 ParU Green Plot. 



4 lbs. Paris green at 25 cts. per lb $ 1 00 



Bordeaux and Paris Green Plot. 



50 lbs. bluestone at 8 cts. per lb $ 4 00 



50 lbs. rock lime at 1 ct. p^r lb 50 



4 lbs. Paris green at 25 cts. per lb 1 00 



$5 50 



