This is the time of year that owners of Eastern red cedars and apple trees will be on the lookout for a fungal disease known as Cedar Apple Rust.

According to OMAFRA’s Publication 310, Integrated Pest Management for Apples,
Symptoms begin to appear at about the same time apple trees are in the pink stage, after a wet period caused by a rain or heavy dew. Galls on the eastern red cedar produce orange telia horns 10-20 mm long that grow from the galls and become orange-yellow and gelatinous.
Symptoms of this rust disease look very different on these two species, but both apple trees and Eastern red cedars (Juniperus virginianae) are affected. This condition can result in complete defoliation and loss of crop.
In apple trees, small, pale yellow spots appear on the upper surface of leaves and on the fruit.
For more information about Cedar Apple Rust, including treatment and management strategies and detailed images of the galls and telia horns on Eastern red cedar, see:
- Cedar-Apple Rust and Quince Rust (Ontario Ministry of Agriculture, Food and Rural Affairs)
- Cedar Apple Rust (University of Nebraska)
(Photo source: OMAFRA)
A new invasive pest is making its way to Durham Region. This pest is especially of interest to growers of apples. OMAFRA has published a 



