SPRAYING FOR CITRUS INSECTS AND MITES IN FLORIDA. 



31 



so that the beneficial fungi will attack those insects which are not 

 killed by the spray. 



Lime-sulphur solution, 32 Baume, 1-50 to 1-75 June to 

 July: The main object of this treatment is to kill rust mites, and the 

 best time for its application varies with the appearance of the 

 maximum number of rust mites. It should be applied before the 

 mites get very abundant and before russeting appears. It will also 

 kill some scales and white flies, but is of little value for that purpose. 



FIG. 21. Heavy coatings of sooty mold on oranges and grapefruit prevent the fruit from 

 coloring normally. The rind remains green beneath the layers of sooty mold. Spraying 

 with a miscible oil breaks up the sooty mold as illustrated, thus giving the sun a chance 

 to color the fruit. 



3. Paraffin-oil emulsions: Government formula, 1 per cent of 

 oil August 25 to October 31: This is the second spraying for the 

 white fly and scale insects. The object of spraying at this time is to 

 kill all the white-fly larvae which are the progeny of the third and 

 last brood. It is this brood which causes nearly all the damage from 

 the white flies, and the earlier they are killed the better it is for the 

 tree. This will also remove the sooty mold from the leaves (fig. 20) 

 and from the fruit (fig. 21) so that the sun can color the fruit. Soda- 



