30 



FARMEES BULLETIN 



the next two weeks. At other times a greater number could be 



present without russeting the fruit. 



Scale insects. For scales spraying should be done before any of 



the limbs or branches are killed or any of the leaves have turned 



yellow. No trees should be left until the center is killed out before 



treatment is given. 

 White flies. The object in spraying for white flies should be to 



keep the sooty mold (figs. 20 and 21) from both the leaves and fruit. 



When each leaf has 



an average of from 

 6 to 10 pupse in the 

 spring, spraying 

 should by all means 

 be given in May. 

 Unless the grower has 

 acquired considerable 

 judgment as to when 

 spraying should be 

 done, it might be well 

 to follow some such 

 scheme as here given. 



SPRAYING SCHEDULE 

 RECOMMENDED. 



The following 

 spraying scheme has 

 been used extensively 

 for four years and gen- 

 erally has given satis- 

 factory results. No 

 hard and fast scheme 

 can be given, how- 

 ever, and the number 

 of sprayings depends 

 to a large extent on 

 the thoroughness of 

 the work and the abun- 

 dance of the pests. 

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

 oil May : The main object of spraying at this time is to kill white 

 flies, scale insects, and to a large extent rust mites, although this 

 treatment must not be relied upon to control the last pest. The 

 spraying should be given after the adults of the first brood of white 

 flies have disappeared and before the appearance of those of the 

 second brood. The fruit should be an inch or more in diameter. This 

 treatment should be given before the beginning of the rainy season, 



FIG. 20. Miscible-oil sprays cause the sooty mold following 

 white-fly attack to break and fall from the foliage and 

 branches. A strong breeze or heavy rain two or three 

 days after trees have been sprayed usually will take off 

 all or nearly all the smooty mold from the tree. (Mor- 

 rill and Back.) 



