Bug FAQSmartweed Borer Moth
Ostrinia obumbratalis · Order: Lepidoptera · Family: Crambidae
Also called: smartweed borer
Source: Wikipedia
It lives across North America, from New Brunswick and Manitoba down to Louisiana and Florida. The caterpillars eat a variety of plants, including corn, ragweed, and other weeds.
Source: Wikipedia
Where it lives
Found throughout North America, from eastern Canada to the southern United States.
Source: Wikipedia
What it eats
Larvae feed on plants such as Polygonum, Ambrosia, Xanthium, Eupatorium, and corn.
Source: Wikipedia
Where it is found in the US
Recorded in 19 of 51 states and DC. Most records: Louisiana, Mississippi, Oklahoma, Kansas, North Carolina, South Carolina, Arkansas, Florida.
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
Questions people ask
What plants do the larvae eat?
They feed on Polygonum, ragweed, cocklebur, Eupatorium species, and corn.
Source: Wikipedia
Where is this moth found?
It is recorded across North America, from New Brunswick and Manitoba down to Louisiana and Florida.
Source: Wikipedia
Same family (Crambidae)
Box Tree MothCydalima perspectalisDamages trees, gardens or crops
Celery Leaftier MothUdea rubigalis
Elegant Grass-veneerMicrocrambus elegans
Hawaiian Beet Webworm MothSpoladea recurvalisDamages trees, gardens or crops
Garden Grass-veneerChrysoteuchia culmellaDamages trees, gardens or crops
Bluegrass Webworm MothParapediasia teterrellusDamages trees, gardens or cropsSources
- Wikipedia: https://en.wikipedia.org/wiki/Ostrinia_obumbratalis
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-29 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-29.