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PEACH INSECTS AND THEIR CONTROL II 



Oriental Fruit Moth 



Damage 



The oriental fruit moth produces two types of damage on peaches, namely in- 

 jury to twigs and injury to fruits. During June and July, when the terminal 

 parts of rapidly growing twigs are soft, they are often attacked by the oriental 

 fruit moth. The larvae tunnel in the twigs and these infested twigs usually have 

 one or more wilted leaves. The damage to the twigs by the early broods is not 

 usually serious except that in severe infestations, it tends to produce a bushy 

 tree instead of one of normal growth. 



Damage to the fruit, however, can be serious. "Wormy" or injured fruit may 

 vary from less than 5 per cent to more than 90 per cent of the crop. "Worminess" 

 is not always apparent from external examination. Fruits infested early result 

 in unsightly scars which exude gum and make the mature peach unsaleable. 



Life History 



The oriental fruit moth overwinters as a larva in a small cocoon beneath bark 

 scales or on the ground. Pupation takes place in early spring and the moths emerge 

 in late May and early June. Noimally, it requires about one month to complete a 

 generation so that the second flight of moths occurs in early July and the third 

 in September. During warm summers, a partial third brood may appear In September. 



Egg laying usually begins 2 to 5 days after the females emerge and will con- 

 tinue for 7 to 10 days or longer. The eggs are laid singly usually on the under 

 surfaces of leaves. Eggs hatch in 3 to 14 days depending on the temperature. In 

 warm weather, hatching occurs in 3 to 6 days. 



The duration of the larval stage in mid-summer is 6 to 15 days but in cool 

 weather may be greatly prolonged. 



The average duration of the pupal stage during the summer is 14 days. 



Hot, humid weather is favorable to the oriental fruit moth. Cool evening 

 temperatures, below 70° F., may cut down on the size of ■ a brood because fewer eggs 

 are laid. 



Control 



Materials for the control of the oriental fruit moth should be applied at 

 Shuck-split, I, II, III, and Later Covers. The Later Cover sprays should be 

 applied at 10 to 12 day intervals beginning about July 10. The effective materials 

 include DDT, Guthion, malathion, parathion, and Sevin. DDT is recommended through 

 III Cover only due to possible excess residue problems. Sevin, a new recomendation, 

 has been effective and is particularly useful late in the season, since it may be 

 used up to 1 day of harvest. 



William D. Tunis 





