Cedar apple rust

Shown here is an intimidating and odd-looking fungal growth attached to a cedar branch. It is called cedar apple rust.

The airborne spores growing on the leaves and fruit of an apple tree will infect the cedar during summer.

After overwintering in the limbs of the cedar, the fungus begins to grow again in spring.

New spores will move again to the apple tree and infect its leaves and fruit.

This is the simplest way I know to describe the cedar apple rust cycle of life.

Probably the best way to prevent this fungus from causing rot in your apples is to cut down any cedar trees within a mile or two of your apple tree.

Since this is usually an impractical measure, the purchase of a sufficient fungicide to spray your apple tree may be in order.

It is always best to spray any fruit tree after all blossoms have fallen from the tree.