Poplar (Populus)-Lettuce root aphid

Pemphigus spp.

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Pest description and crop damage Aphid cause flask-shape galls on leaf petioles. Galls are not hazardous to trees.

Management-chemical control

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For more information

Johnson, W.T. and H.H. Lyon (1991), Insects That Feed on Trees and Shrubs, 2nd ed., Cornell University Press (p. 460).