Bug FAQOak Wart Gall Wasp
Callirhytis quercusfutilis · Order: Hymenoptera · Family: Cynipidae
The oak wart gall wasp lives on white oak trees, with one generation forming galls in the bark at the tree’s base and another making leaf galls between veins.
Source: Wikipedia
Where it lives
The sexual generation makes galls on white oak leaves, between veins and slightly raised on both leaf surfaces.
Source: Wikipedia
Life cycle
The asexual generation lives in the bark of the host tree. Larvae receive nutrients through thin radiating fibers that connect their chamber to the gall wall.
Source: Wikipedia
Where it is found in the US
Recorded in 42 of 51 states and DC. Most records: California, Virginia, Massachusetts, North Carolina, Texas, Ohio, Georgia, New York.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Months it is reported in the US
Source: GBIF
More photos
Same family (Cynipidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Callirhytis_quercusfutilis
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-23 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.