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Picture of the Week
for 6 September 2000



Cynipid Gall Wasp

The P&PDL recently received this white oak sample and have received a few phone calls with similar descriptions on oaks. The galls look like clusters of tiny acorns on a branch and were caused by a cynipid gall wasp. These tiny insects cause a gall to form around them as they develop. Because the growth is actually plant tissue, it does little damage to the tree. No chemical controls are recommended. Pruning out and destroying galls will aid in reducing the population next year.
- Tim Gibb

Cynipid Gall Wasp on White Oak Cynipid Galls Close-up of Wasp Larva in Gall
Cynipid Gall Wasp on White Oak Cynipid Galls Close-up of Wasp Larva in Gall

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