Bug FAQBlackberry Knot Gall Wasp
Diastrophus nebulosus
The insect is called the blackberry knot gall wasp. It forms its galls on the plant Rubus flagellaris.
Source: Wikipedia
Where it lives
Its host plant is Rubus flagellaris.
Source: Wikipedia
Where it is found in the US
Recorded in 32 of 51 states and DC. Most records: Virginia, North Carolina, Maryland, Pennsylvania, New Jersey, Ohio, Tennessee, Georgia.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in United States. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
What plant does the blackberry knot gall wasp use?
It uses Rubus flagellaris as its host plant.
Source: Wikipedia
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Diastrophus_nebulosus
Look it up elsewhere: iNaturalist · BugGuide · Wikipedia
Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-24.