294 REPORT OF STATE BOARD OF HORTICULTURE, 



HOW AND WHEN THE WORMS LEAVE THE FRUIT. 



When the caterpillar is ready to leave the fruit it pushes away the 

 plug of pellets, described above and shown at a in Fig-. 1.34, and crawls 

 out, leaving- a round, blackish-looking- '' worm hole " as shown atb in the 

 same figure. When this exit hole is found, one can easily tell whether a fruit 

 still contains the worm or not, by the presence or absence of the plug of 

 pellets. It is said that the worms leave the fruit mostly at night. 



If the fruit has already fallen to the ground, the caterpillar proceeds to 

 crawl to some secure and suitable place in which to begin its preparations 

 for becoming a moth. Those worms which leave the fruit on the tree were 

 seen by LeBaron in the orchard by lamplight to either let themselves down 

 to the ground by a silken thread, which they spun as they went, and then 

 crawl back to the trnnk ; or they crawled from the apple onto the branch 

 and thence down the trunk. Cook, from some experiments made in 1875, 

 thought that the worms seldom, if ever, dropped from the tree to the 

 ground ; and that at least one-half of them did not descend to the ground at 

 all. Trimble records collecting a number of worms and putting them on 

 the ground in the vicinity of an apple tree. They crept around at random 

 for a little while, but, if not too far off, most of them were soon seen going in 

 the direction of the tree. 



The date when the worms which enter the fruit in the spring get full- 

 grown and leave, can not be stated definitely. For the irregularity in the 

 appearance of the moths at that time is so great that oftentimes some of the 

 earliest worms will be ready to leave when others hatched from later eggs 

 will be just entering the fruit. In the latitude of Saint Louis, Riley records 

 finding full-grown worms as earily as the fifth to the tenth of June. Usually, 

 however, the early summer brood of worms in the latitude of New York do 

 not mature until July and later. From the first of July until winter sets in, 

 one can usually find at any time worms of all sizes in the fruit ; and large 

 numbers of them do not leave the fruit until it has been barreled or stored 

 for winter. 



THE COCOON. 



Where it ift made — After leaving the fruit, the apple worm next devotes 

 its energies to finding a suitable place for its cocoon, in which to undergo its 

 further transformations. Many of them find their way to the trunk, larger 

 branches, or into the crotch of the tree, where they crawl into any crevice 

 they can find under the rough, loose bark. Other worms find suitable 

 quarters on near-by fences or trees, in piles of rubbish, under boards or 

 chips, in stumps, in fact, almost anywhere, except in the ground or among 

 the grasses or weeds.* In November, 1875, Beal made a very careful exami- 



* Mr. Crawford records tin instance in Australia where the worms tooli refuge in tlie 

 pith of old raspberry canes growing under apple trees ; twenty worms were found in one 

 of these canes. In 189(), several raspberry canes, which had been badly infested with the 

 cane-borer, were sent us from Ohio. In the pith, we found several apple worms snugly 

 tucked away in their cocoons. In this case, tlie worms had evidently found an easy 

 entrance to the canes through the large hole made by the borer when it emerged as a. 

 beetle. While breeding the insect here in the insectary, we have had the worms burrow 

 into pieces of cork and work their way into books to spin their cocoons. Cooke says the 

 cocoons are often found in (.California from one to six inches below the ground on the 

 base and roots of the smooth-barked trees. 



