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Ocellate galls on maple

If you receive the NCSU Pest News you already learned about ocellate gall midge.  However, I found a new infestation this week that showed different developmental

Developing gall before red center and ring appear. Photo: S.D. Frank
Developing gall before red center and ring appear. Photo: S.D. Frank

stages so I though I would share the pictures.  You can see light green circles on leaves in which the larvae is just developing, darker circles with red edges that have larvae inside.  Then there are darker ones that have emergence holes int he bottom.  The ocellate gall midge, Acericecis ocellaris causes an ocellate (single-spotted), pale green to yellow, often bright red-margined gall.  Galls are 5 to 6 mm in diameter and occur primarily on foliage of red maples but also A. saccharinum,

Ocellate galls at different stages of development. Photo: S.D. Frank
Ocellate galls at different stages of development. Photo: S.D. Frank

A. spicatum, and A. pennsylvanicum.  I found galls this week on trees in central Georgia so if you have not seen the here yet you will soon.  Galls typically appear in May and contain a single, translucent midge larva. Larvae exit the gall and drop to the ground to overwinter as pupae.  These are actually quite attractive critters that could even improve the appearance of trees. Just think, if someone bred a tree with yellow and red eye-shaped dots it would be all the rage.  That said, these midges usually only occur a few at a time and will not harm tree health.  Find out more about maple pests in a free e-book: http://ecoipm.com/extension/extension-resources/