POTATO SPRAYING AND DUSTING. 



9 



that not a single specimen was observed in the northern parts of the State. Its 

 occurrence in the south can be associated with the greater prevalence of grasshoppers, 

 on the eggs of which this Meloid beetle feeds in its larval stages. 



Throughout the season the plots sprayed with Bordeaux mixture gave every 

 promise of large yields ; the plants had a healthy deep green colour, while 

 they retained their vigour at the end of the season for almost ten days longer than those 

 in the other plots (Plate iii, figs. 1 and 2). From an examination made on 24th July, 

 the order of value of the various treatments was as follows : 



1. Bordeaux mixture and arsenate of lead. 



2. Sulphur and lead arsenate mixture. 



3. Kil-Tone. 



4. Lead arsenate. 



That this order, as determined by the appearance of the foliage, had some significance, 

 can be judged from the yields obtained when the potatoes were dug on 10th August. 



Table II. 

 Yield of Tubers {Firsts and Seconds) at Elmer. 





Yield in bushels per acre. 







Nature of Application. 



Series I. 



Series II. 



Average of the 2 series. 





Ists. 

 201-5 



2nds. 



Ists. 

 254-15 



2nds. 

 44-2 



Ists. 



227-82 



2nds. 



Bordeaux and Lead Arsenate 



51-35 



47-78 



Lead Arsenate (Control) 



/102-7 



(180-8 



154.7 



30-55 



41-9 



34-7 



34-7 



199-2 



I213-85 



232-05 



218-40 



191-3 



39-9 

 21-4 

 24-6 



> 180-55 



32- 175 



Sulphur and Lead Arsenate . . ■ 187-4 



26-6 



202-9 



30-6 



Kil-Tone 



161-84 



38-35 



37-5 



176-58 



37-92 



Avg. gain in bushels per acre of firsts on Bordeaux plots over control, 47 - 27 

 Avg. gain in bushels per acre of firsts on Bordeaux plots over sulphur, 24-92 

 Avg. gain in bushels per acre of firsts on Bordeaux plots over Kil-Tone, 51-24 



Avg. gain in bushels per acre of seconds on Bordeaux plots over control, 15-60 

 Avg. gain in bushels per acre of seconds on Bordeaux plots over sulphur, 17-18 

 Avg. gain in bushels per acre of seconds on Bordeaux plots over Kil-Tone, 9 - 86 



Avg. gain in bushels per acre of sulphur and lead arsenate plots over 



control (firsts and seconds) . . . . . . . . . . . . 20- 77 



Avg. gain of sulphur and lead arsenate plots over Kil-Tone . . . . 19-00 



