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EssiG (E. 0.). Important Dried Fruit Insects in California. -MOily. 

 Bull. Cal. Sla'e DepL Agric, Sacramen'o, ix, no. 3 (Supplement), 

 March 1920, pp. 11^-125, 5 figs. 



There are not many msect pests of dried fruits in CaUfornia, but 

 the few that occur are responsible for a great deal of damage and 

 loss. The larvae of the moths attacking dried fruit are easily detected 

 by their habit of webbing the fruit and the container, and by the 

 presence of the thick white cocoon that they spin for pupation. The 

 moths, attracted by the scent of the fruit, oviposit directly upon it 

 whenever possible, and the young larvae generally manage to gain 

 access to it. Each generation requires from one to two months, so 

 that reproduction is rapid. The commonest species is Plodia inter- 

 jnmdella (Indian meal moth), which breeds in all cereal products, 

 nuts, seeds, and many kinds of dried foods. Owing to its general 

 feeding habits this insect is very troublesome in public warehouses 

 and stores. Pupation frequently occurs in corners and crevices of the 

 packing houses and the moths can survive from crop to crop, so that 

 a house once infested will remain so unless thoroughly treated. 

 Ephestia cautella, Wlk. (fig moth) has been repeatedly introduced into 

 America in Smyrna figs, and has become established in many 

 localities, but has not yet become a pest in Cahfornia. Watch should 

 be kept for its appearance. 



The larvae of beetles infesting dried fruits may be distinguished 

 m'er alia by their inability to spin webs. They work in the fruit, in 

 which they pupate, the adults being very active and strong fliers. 

 The most injurious beetle is Cnrpophilus hemiplerus, L., the larvae of 

 which reduce the fruit to a mass of fine powxler. Fruit frequently 

 becomes infested while still on the trays in the drving yards, and the 

 pest is thus carried to the packing houses. It is particularly abun- 

 dant in the central valleys and southern parts of the State. 

 [R.A.E., A, iii., 681]. Silvanus surinamensis, L. (saw-toothed grain 

 beetle) is also very injurious at times, particularly to figs, destroying 

 not only the fruit, but also boring holes in the packages. 



Ihe most important factor in control of all these insects is cleanli- 

 ness. With the exception of C. hemiptenis, infestation almost always 

 occurs in the packing house or in a storehouse after packing. All 

 packing houses should therefore be thoroughly cleaned prior to harvest 

 time. Fruit that has been kept since the previous season should be 

 carefully inspected, and if any infestation is found, the entire house 

 should be thoroughly treated. 



General directions for fumigating packing-sheds, storehouses, or 

 piles of fruit-boxes under canvas, with either carbon bisulphide or 

 hydrocyanic acid gas are given. Much success has been obtained 

 with a vacuum fumigator in which materials are placed for fumigation 

 after the air has been drawn off. The advantages of this method 

 include thorough penetration of the gas into the densest materials, 

 quickness of killing and operation, and ease and safety in handling. 

 Carbon bisulphide, hydrocyanic acid and dry steam can be used in 

 this way. The equipment is expensive, but is lasting and efficient. 



Avery general treatment of insects in mills, packing houses, etc., 

 is by heat, a temperature of 140° to 180° F. being maintained for 

 several hours. This is sufficient to kill larvae, adults, and generally 



