Cedar Apple Rust: How To Spot It, And What To Do About It

Cedar apple rust is a fungal infection that is passed between cedar and apple trees. If you live in an area where cedar trees are prevalent and you have one or more apple trees on your property, then it pays to be aware of the symptoms and recommended treatment methods for this disease. Otherwise, you could find that your entire apple crop is lost to cedar apple rust.

Signs of Cedar Apple Rust

  • The Leaves: The first signs of cedar apple rust typically appear on the leaves of the tree. Yellow spots, which may be round or oddly shaped, appear on the top surfaces of the leaves. Typically, the spots first appear soon after the tree blooms, but they may not become plentiful enough that you notice them until the end of spring. As summer wears on, the leaf spots will begin to develop brownish clusters that, if you look closely, resemble piles of thread.
  • The Fruit: If the infection is minor, the symptoms may not spread to the fruit in the first year. However, a moderate to severe infection will cause brown and yellow spots to appear on the apples. Some apples may remain edible, though not as attractive, while others may have more substantially damaged skin and flesh and will thus be unusable.

Treating Cedar Apple Rust

If you notice signs of cedar apple rust on the leaves, it's important to take care of the issue right away before the fungus attacks the fruit. If you let the condition proliferate, your tree may never recover.

Begin by having your tree sprayed with a fungicide. One that contains copper or sulfur is likely to be the most effective. Then, have badly infected branches pruned away. This may mean losing some of your apple crop this year, but it will save the tree and your apples in subsequent years, so it is a wise sacrifice to make.

When fall comes, be sure to clean up any fallen apples and leaves promptly, as they can provide an over-winter home for the fungus and lead to reinfection next spring. The following spring, have your tree pruned well before it blooms, so any branches that seem to be ailing can be removed. Also, have the tree sprayed with fungicides every few weeks, beginning before blooming and continuing until the fruit is ripe.

If you're planting new trees in an area where cedar apple rust is common, it's wise to plant disease-resistant varieties like Liberty, Freedom and William's Pride. This way, the chances of your tree developing the infection will be greatly reduced. If you have any questions, contact a company like Emile's Landscaping & Tree Service Tree Service.