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The Apply Worm

Apple worms in core of apple. Usually only one worm appears in an apple. Note the decaying of the apple.

This is perhaps the most destructive insect pest attacking the apple. Every year, that we have a good apple crop, there are thousands of bushels of wormy apples which are practically worthless. This means an actual loss of thousands of dollars a year to the apple growers of this country.

For this reason alone each child should come to know the life history, habits and injury of this pest. It is most destructive to the apple though the pear comes in for its share.

The codling moth slightly enlarged. (From Slingerland).

Every country child and many of those of the cities, are familiar with this worm for they often bite into it while eating apples. The small worms crawl down in the blossom end of the young developing apple and from there bore into the pulp and eventually reach the core of the fruit. They stay in the apple about six weeks when they eat a hole out to the surface and crawl down to the trunk where loose bark offers a hiding place. Here they spin their cocoons and change to a small, brown, plump pupa and after a few days the winged moth emerges. The moth is very small and is not often found by one not acquainted with it. They come out during late June and early July when they lay eggs for a second colony of worms which again enter the fruit and destroy more of it. These worms of the second brood are usually mature and leave the fruit about the time apples are picked in the fall in central Missouri. They escape and soon spin cocoons in which they pass the winter. Early in the spring these change to pupae and later the moths come out. They appear about the time apples bloom in the spring and lay the eggs for the first worms which enter in great numbers at the blossom end.

Apple blossoms at about the right stage for receiving the first and most important arsenical spray for the control of the apple worm.

This in short, is the life story of the pest through the year. Little can be done to destroy the pest after it gets into the fruit, therefore remedies must be applied to destroy the worm before it gets into the fruit. All orchards should be sprayed with a poison in the spring before the worms appear. Since most of them enter by way of the blossom end, it is necessary that the poison be put into the blossom end. To do this spray at once after the blossoms fall, repeat after two weeks and spray again in July to kill the second brood of worms. The protection of woodpeckers and sapsuckers will also help as they feed on the worms under the bark.