﻿STRAWBERRY ROOTWORM ON GREENHOUSE ROSES 



41 



Tabm; 15. — Effect against the strawberry rootworm of miscellaneous treatments 

 on larvce and pupw in soil of potted rose plants 



Material and amount per plant 



Borax, 1 gram in J^ pint water '-. 



Borax, 2 grams in ^ pint water 2 . 



Orthodichlorobenzene, 3 c. c.' 



Mercuric chloride (1-800), H pint 2 



Wood ashes, soil covered Ji inch 



deep < 



Do.s 



Tobacco dust, soil covered % inch 

 deep ' 



Lye (sodium hydroxide), 1 tea- 

 spoonful in H pint water • 



Lye (sodium hydroxide), 1 tea- 

 spoonful dry and then watered «. 



Nicotine sulphate, 2 drops in 225 

 c. c. water 2 



Kerosene nicotine oleate, 8 e. c. in 

 250 c. c. water « 



Kerosene nicotine oleate, 16 c. c. 

 in 250 c. c. water 3 



Checks[(no treatment) 



Do 



Do 



Do... 



Number 

 of— 



Lar- 

 vae 



Pu- 

 pae 



Pe- 

 riod 

 after 

 treat- 

 ment 





 



10 I 

 5 





 10 



10 















10 



10 

 10 



7 

 5 

 4 



Days 



Condition when examined 



Larvae 



Dead 



Alive 



Miss- 

 ing 



Con- 

 trol 



P.ct. 



5 







100 









 





 30 

 50 







60 



90 

 

 

 

 



Pupae 



Dead 



Alive 



Miss- 

 ing 



Con- 

 trol 



P.ct. 











100 









 20 



















50 



90 

 10 

 

 

 



» One larva pupated. 

 2 Ineffective. 



3 Effective. 



* Two larvae pupated. 



5 Slightly effective. 

 « Fairly effective. 



Table 16. 



-Effects of paradichloroienzene soil treatments on larvce and pupce of 

 the strawberry rootworm buried in pots 









Period 

 after 

 treat- 

 ment 



Condition when examined 



Amount 



of 

 material 





Larvae 



Pupae 





Larvae 



Pupae 



Dead 



Alive 



Missing 



Control 



Dead 



Alive 



Missing 



Control 



Orams 

 2. 



25 

 25 

 10 

 20 

 10 



.10 

 10 

 

 

 4 



Days 

 6 



6 

 5 

 6 

 5 



24 

 25 



5 

 17 



6 





 

 

 

 



1 

 

 5 

 3 

 4 



Per cent 

 96 

 100 

 50 

 85 

 60 



10 

 10 

 

 

 4 



ooooo 





 

 

 

 



Per cent 

 100 



3 



100 



4 







4 







8 



100 







The results obtained with paradichlorobenzene in preliminary tests 

 were so satisfactory (see Table 16) that this material was used in 15 

 plots in an infested bed. In 10 of these the larvae and pupae were 

 counted and their condition was noted in order to determine the in- 

 secticidal effect of this chemical. These data are presented in 

 Table 17. 



