The main apple insect pest in most home gardens is the apple maggot (Rhagoletis pomonella), a small fly whose larva burrows into the fruit and makes it inedible. But you can control this pest if you know it weakness. You see, the female fly loves red! Given the choice of tiny green apples and a nice big red apple, she will almost certainly choose the red one. And the home gardener can turn this affection to his advantage.
Just take a red ball (or paint a ball red) and hang it from the tree. Do this after the petals have fallen, but before the unripe apples are visible, usually before the end of June. Now apply a non-drying glue (“Tanglefoot”, widely available in garden centers, is the usual choice) to the outside of the ball. The trap is now set.
If you’re not interested in making your own red ball trap, you can also purchase commercial traps. They too are shaped like red balls and come with their own non-drying glue And they’re easy to find: most garden centers and even some hardware stores offer them. Some are even equipped with an attractant that makes them more effective: a fruit essence that attracts the apple maggot flies.
Or use a real apple! Simply coat a apple from the supermarket with Tanglefoot or a similar glue and hang it from the tree.
How the Trap Works
When the apple maggot fly sees the sticky red ball, it will tend to visit it rather than the real apples nearby which are still small and green… and it remains stuck on the trap. In years where the apple maggot population is low (it varies widely from season to season), a single trap will see that up to 98% of the fruit is free of maggots. When the population is high, however, you may need to multiply the traps, placing up to five red balls in each tree… and also, you’ll have to clean the balls when as they become covered in flies. Just apply another layer of glue and hang them back in the tree.
Several studies show that the trap red ball will be even more effective if you accompany it with yellow sticky traps, also known to attract insect pests. Place the yellow trap on the outer edge of the tree, in full sunlight, and the red ball trap in among the foliage, but still well exposed, and the poor pest won’t know what hit it!
There is also trap that combines both methods. The Ladd trap, named for its manufacturer (www.laddresearch.com), consists of a red ball surrounded by a yellow trap and includes an attractant as well. It is, apparently extremely effective: truly the Cadillac of apple maggot traps. However, it is also sold at Cadillac prices: $29.95 US per trap on the Gardens Alive website.
Hang a few red balls from your apple trees this summer. It can save you a lot of disappointment.