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Summary
DescriptionLeaf galls on crack willow - geograph.org.uk - 1449425.jpg
English: Leaf galls on crack willow. These reddish swellings on crack willow (Salix fragilis) are galls, produced by the sawfly species Pontania proxima (several Pontania species occur on willows and sallows, so, as usual, a vital first step is to identify the host plant). Sawfly larvae develop within the swellings.
[The identification of the gall is based on the keys in the handbook "British Plant Galls" (2002). The taxonomy of gall-causers on willows is, at the time of submission, still in flux. When appropriate, I will update this item to include any change to the name of the species.]
The tree on which the galls occurred was in this area: 1449370.
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== {{int:filedesc}} == {{Information |description={{en|1=Leaf galls on crack willow These reddish swellings on crack willow (Salix fragilis) are galls, produced by the sawfly species Pontania proxima (several Pontania species occur on willows and sallows,