insect prevention on apple trees

Asked August 3, 2018, 9:26 AM EDT

Hello, I'm looking for some help with insect prevention on apple trees. I'm a home gardener trying to raise some apples. I have a Fuji, Honeycrisp & Liberty apple trees. I can't seem to be able to defeat them no matter what I try. This is what I'm currently doing: 1. Dormant spraying with Neem Oil 2. Spraying with Bonide Fruit Tree Spray during the growing season 3. Hanging apple maggot traps in the trees. I attached a photo of a couple of the apples. Can you help me with my issues? Many thanks for any help you can provide.

Livingston County Michigan apple insects

4 Responses

The apples in the photos look like they were attacked by plum curculio and either tarnished plant bug or rosy apple aphid soon after bloom.
Plum curculio egg laying scars are the half moon shaped and small circular brown spots.
Plum curculio feeds in the early spring and then lays its eggs during the first really warm spell in the spring when we have temperatures into the 70s and warm nights. The misshapen fruit is caused by tarnished plant bug feeding on young fruit
or by rosy apple aphids feeding on the fruit after bloom
The more I look at it the more I think it was rosy apple aphid because the fruit is so misshapen and tarnished plant bugs usually leave a dimple in the fruit.
To control the aphids you need to do a dormant spray with a dormant oil to suffocate the aphid eggs on the tree. Neem oil is not a dormant oil. It is used as a insect repellent during the growing season. The dormant oil is a highly refined petroleum oil which is sprayed on the tree just as it starts growing and suffocates overwintering insects and insect and mite eggs. You can buy some in a garden store.
For the plum curculio you probably did not start your insect sprays soon enough in the spring. Begin you sprays when the fruit are about the size of your little fingernails.
If you search the internet for 'home tree fruit spray schedule' you will find that many universities have these posted as PDF files. The are all pretty good.

Thanks mark

What time of year is best for dormant spray?

In your location, March.
Best timing is just as the tree and buds begin growth. Depending on the oil you use try to apply just as the first buds are opening.Double check the weather and be sure it is not going to freeze for the next two days. If is is going to freeze, wait until you have a two day window. Once the leaves begin to unfold it get late and you need to reduce the oil by half.

Thanks for all the help