20 MISSOURI AGRICULTURAL EXPERIMENT STATION BULLETIN 176 



only after careful search. The eggs hatch in about a week, depending upon the 

 temperature. 



LARVA. The young larva, like the egg is small and difficult to see with the 

 unaided eye. If hatched near fruit the larva in time may reach the fruit and 

 gain entrance. In time it makes its way to the core and later feeds on the 

 seeds and surrounding part of the apple. The larva at first is light but usually 

 takes on a more or less distinct pink color. It feeds for about one month and 

 when full fed is about three fourths an inch in length. On maturing the larva 

 leaves the fruit, spins a cocoon in some protected place, such as under the bark 

 of the tree and in time pupates. 



PUPA. The pupa is a small brownish object very similar to other related 

 species. It is about one-half an inch long and is found inside a small but rather 

 firm cocoon. In the. summer it usually remains in the pupa stage for from 

 about one week to ten days and 1 then emerges as the adult. 



The insect passes the winter in the larval stage in the cocoon protected 



under the bark of the tree or about 

 apple boxes, pens or where apples 

 were stored for a time after picking. 

 The larvae pupate just before apples 

 begin to bloom and the adults emerge 

 soon after the blossoms drop. Eggs 

 are soon deposited and the first 

 young larvae begin to hatch about 

 two weeks after the blossons are all 

 off. 



Those worms which gain access to 

 fruit become fullfed in about a 

 month, when they leave the fruit, 

 spin their cocoon and later emerge 

 as the summer brood moths. In 

 central Missouri these usually appear 

 on wing during the first ten days of 

 July. However, they may be has- 

 tened or retarded in thier develop- 

 ment by temperature so each fruit 

 of emergence of the summer brood 



FIG. 23. Codling moth; stages of devel- 

 opment and injury to apple (After Riley) 



grower 



should determine the date 

 of moths in his own orchard. This he can do either by collect- 

 ing a few wormy apples in June, and putting them in a tight box or 

 other container where later the emerging of the moths can be observed or by 

 putting rag bands on a few trees under which the worms will collect to pupate, 

 and where the first emerging of adults can easily be determined. It is impor- 

 tant to know when the July or summer brood of moths emerge so as to prop- 

 erly time the July application of spray. 



Where a third brood develops the moths emerge late in August and the 

 small worms may be found in the fruit at picking time in the fall. In the 

 southern part of the state spring opens earlier and the pest has a longer breed- 

 ing season. This permits the pest to develop more broods and to do more 

 damage to the fruit. 



During the present spring, summer and fall conditions in Missouri have 



