Growth on grape vines

Asked June 15, 2020, 3:26 PM EDT

Found this new odd growth on the grape vines just within the past week. We have not had it or noticed it ever before. We have had black rot and treat for that and have no problems with that anymore, so this is new. It is on the leaf as well af the vine itself. Best advice on what it is, and what to do. Thanks as always

Harford County Maryland

1 Response

This appears to be a gall formed by a midge (small fly) called Grape Tumid Gallmaker or Grape Tomato Galls. While unsightly, they are generally harmless to the plant's overall health and no control is necessary. You can learn more about this pest on this fact sheet by Cornell: https://ecommons.cornell.edu/bitstream/handle/1813/43134/tumid-gallmaker-FS-NYSIPM.pdf?sequence=1

Miri