On an apple or crabapple tree, it appears as circular yellow lesions on the leaves shortly after they bloom. In late summertime, the brownish clusters of threads or cylindrical tubes appear under the spots on the leaves, twigs, or fruits.

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In terms of how long the disease lasts, galls appear seven months after the infection first starts. They start to turn into gelatinous masses after 18 months. Then, golf-ball-like depressions appear on the gall, which make way for telial horns the following spring. In the spring rain, the brownish telial horns get longer and turn bright orange. After they release their spores, the horns collapse, dry, and fall off. While the galls then die, they remain attached to the tree for at least another year. The infection is much more obvious in spring when the gall is covered in gelatinous masses.

There are many ways to manage the infection. You can prune off the areas that are infected. You can also leave it alone since it does not kill trees but only disfigured plants where the twigs might be affected. There are also preventative methods; to get preventative fungicides or resistant, apple varieties also exist.

All in all, this does not really affect trees too badly! However, it is important to be aware of it so you know what to do when it pops up in your backyard! Share this with others so they can also know what this infection is!