Growing good apples is a little tricky because of all of the pests that feed on them and cause damage to the fruit.
We discussed the Curculio a couple of posts ago, this time we need to talk about another major pest on apples, the Codling Moth. This is the proverbial “worm in the apple” that you see in those old-timey cartoons. It is not a worm as such but rather is the larva of a moth.
The Codling Moth is not a very attractive moth as seen in this photo taken by MSU Horticulturists.
Normally there are two generations of this pest in our area although in some years we see a third generation as well depending upon that season’s weather.
According to scientists who measure certain weather and other conditions, the Codling Moth larvae are hatching from their eggs right now. After the larvae hatch, they will begin to burrow into the fruit. Once they get inside the fruit they cannot be killed because insecticides cannot reach them.
Codling Moth damage on apple. (MSU photo)
Timing is very critical for controlling Codling Moth effectively since the larvae begin to burrow into the fruit just hours after hatching. Large commercial orchards use sophisticated traps to monitor adult moths. With that information they can determine when egg laying happens and apply their sprays accordingly. For the rest of us we have to pretty much rely on our 10 day to two week spray schedule to do the trick.
Michigan State University Extension in Van Buren County has a very detailed web page regarding this pest.
Another generation of Codling Moth can be expected in August.
Bob