Leaf galls on common alder
Introduction
The photograph on this page of Leaf galls on common alder by Lairich Rig as part of the Geograph project.
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Leaf galls on common alder
Image: © Lairich Rig Taken: 12 Sep 2008
The central leaf, with discoloured bulges, is affected by a mite, probably Acalitus brevitarsus. The lower surface (not shown here) is covered with what seems to be a creamy-coloured powdery mass, but is really a dense mass of hairs (called an erineum) whose growth is induced by the mites.
Images are licensed for reuse under creativecommons.org/licenses/by-sa/2.0
Image Location
Latitude
55.95547
Longitude
-4.557892