Gall-Making Aphids (image) Howard Hughes Medical Institute Share Print E-Mail Caption Hormaphis cornu aphids feed on witch hazel leaves and coax the plants into making galls. Credit David Stern Usage Restrictions Must use credit. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.