70 FUMIGATION FOE THE CITRUS WHITE FLY. 



Paga 



Fumigation against citrus insects, history 7-8 



white fly, absence or elimination of food plants other than 



citrus favorable 9-10 



appearance of dead larvae and pupse 50-51 



chemicals, cost 58 



handling, and protection from mois- 

 ture 25 



proportion of water and acid 25-27 



purity required 25 



concerted action favorable 9 



conditions favorable or necessary to good results. . 9-14 



cost compared with spraying 62-63 



density of gas at various heights above ground. . 51 



dosage requirements with bell or hoop tent 49-50 



sheet tent 40-49 



economy of treatment 59-63 



effect on trees and fruit 51-54 



equipment 14-24 



expense 56 



history 7-8 



isolation of grove favorable 9 



losses prevented thereby 59-60 



measuring trees 30-35 



meteorological elements favorable 11-13 



method of generating gas 35-36 



handling bell tents 29 



sheet tents 27-29 



methods of computing cubic contents of tented 



tree 39^0 



dimensions of tented trees 39-40 



miscellaneous experiments and observations 50-54 



requirements. 22-24 



nursery stock for shipment 54-55 



poles for handling; tents 20-21 



precautions 55-56 



procedure 27-38 



proportion of water and acid 25-27 



season of year favorable 10-11 



table of dosage 66-68 



tents, care 19-20 



construction 15-19 



mildew-proofing, oiling, and i:)ainting 19-20 



shrinkage 17-18 



styles 14-15 



time required 38-39 



trees, regularity of setting favorable 14 



size favorable 14 



small, in the grove 54 



nursery 54 



uprights for handling tents 21 



versus natural control 63-65 



work routine 36-38 



Fungous diseases in control of white fly 64-65 



