332 



THE MONTHLY BULLETIN. 



cyanide or ^ for sodium cyanide. The smaller dosage is recommended 

 only where there is an even hatch of very young scale insects. 



Purple, Red, Yellow Scale. — Use dosage schedule No. 1 for potassium 

 cyanide and No. f for sodium cyanide. 



Mealy Bug. — The same dosage as for black scale gives almost as good 

 results as the heavier doses. 



LENGTH OF EXPOSURE. 



The time required to complete the generation of the gas is not long, 

 but it is advisable to leave the tents upon the trees for at least forty-five 

 minutes after the dosage is placed under the tent. Some prefer thirty 

 minutes, while others insist upon a full hour. 



VENTURA COUNTY HORTICULTURAL. COMMISSIONER 



E. O. ES3IG 



FUMIGATING SCHEDULE FOR BLACK SCALE 

 SODIUM CYANIDE 



NOTE. — Quarter and hall ounces are omitted to 

 froporttons for mixing chemlcalc — Sodium Cyai 



make 

 nide 1 



the schedule more practical for 

 , Sulphuric Add I'.'j. Water 2. 



fictd conditions. 



Fig. 318. — ^Dosage schedule No. J for black scale using- sodium cyanide as prepared 



by Woglum. (Essig, P. C. Jr. Ent.) 



