CONTROL OF DRIED-FETJIT INSECTS IN CALIFORNIA. 



9 



Of these cartons 16 were sealed as shown in Plate III, figure 1, 

 and 16 left unsealed. Of the unsealed ones, 8 were so prepared that 

 the wrapping paper was slightly torn. This condition is one fre- 

 quently found in packages of figs put up by the girls in the packing 

 house. 



The 32 cartons prepared as described above were brought to 

 Sacramento and placed in an insect-tight box in which were then 

 placed large numbers of larvse and adults of Plodia inter punctella, 

 Carpophilus Tiemipterus, and Gnathocerus (Echocerus) maxillosus Fab. 

 The box was then sealed so that the insects could not escape, and 

 they were given every chance to infest the cartons. 



At the conclusion of these experiments, April 16, 1914, all but two 

 of the unsealed 

 cartons were found 

 to be infested, 

 while the sealed 

 ones showed no 

 evidence of insects 

 having entered. 

 It was observed 

 that the larvse of 

 Plodia interpunc- 

 tella had in some 

 places broken 

 through the thin 



paper used to wrap the bricks of figs before they are placed in the 

 cartons. 1 It had previously been supposed by the packers that this 

 paper if preserved intact would prevent insects from reaching the 

 fruit. 



The foregoing experiments will serve to prove the efficiency of a 

 sealed carton in protecting packed dried fruit from insect attack. 



SEALED PACKAGES FOR DRIED FRUIT. 



Packages of dried fruit weighing less than 5 pounds are so nearly 

 the size of the cartons used for cereals that, except for the high labor 

 cost of sealing, the method used with the cereal carton could be 

 readily applied to dried fruits. With the 10, 25, and 50 pound pack- 

 ages, however, the cost of such sealing is excessive, and the wooden 

 boxes used can not be thus sealed to advantage, as the seal is easily 

 broken by rough handling. To obviate this difficulty a light paper 

 carton fitting inside the wooden box, and sealed before the top was 

 nailed on, was constructed, but the cost of these cartons and the 

 additional labor required to pack them prohibited the employment 



Fig. 4. — Diagram of carton, showing method of applying label to protect 

 inclosed cereal from insect attack. (Author's illustration.) 



1 A heavy paraffined paper appears effective in preventing insects from eating through. 



