Apple Fungus

Asked January 7, 2017, 4:43 PM EST

I have a few apple trees. One has been attacked by a white, mosey looking fungus that looked like insect eggs being placed on the branch. Upon further examination the fungus appears to have eaten into the bark of the branch causing the branch to swell at the point of infestation. I have never seen this before and would like to know what I can do to stop the spread and/or get rid of it. Thank you, CarlB.Jensen@gmail.com

Yamhill County Oregon

1 Response

Long-distance diagnosis is challenging, at best. My best wild guess at this point, based on your description of a swelling on the branch where you see the white material, is woolly apple aphids.

Several images would increase the odds of a helpful response. Useful pictures would include the tree and it surroundings; a mid-distance view of a typically affected branch, and a close-up showing as much detail as possible. If you are unable to take and email digital images, you might ask a friend, neighbor, or relative for help.

Or you can take a sample to the Yamhill County Extension Office for a first-hand identification. A good sample is a 12 to 18-inch long branch with several of the enlarged growths. The office is at 2050 NE Lafayette Ave, McMinnville, OR 97128; open Monday through Friday. Phone 503-434-7517 to ask when the Master Gardeners are available.