Bug FAQAlfalfa Webworm Moth
Loxostege cereralis · Order: Lepidoptera · Family: Crambidae
Also called: Alfalfa Webworm
Source: Wikipedia
The alfalfa webworm moth has a wingspan of about 30 to 34 mm. It occurs across Canada from Quebec to British Columbia and extends southward to Mexico.
Source: Wikipedia
Size
The adult’s wingspan measures roughly 30 to 34 mm.
Source: Wikipedia
Where it lives
It lives from Quebec west to British Columbia and south to Mexico.
Source: Wikipedia
What it eats
The larvae feed on alfalfa and many other crop and weed species.
Source: Wikipedia
When you see it
Adults are on the wing from March through October, with a shorter period in Alberta.
Source: Wikipedia
Where it comes from
Its range includes much of Canada and extends into the United States and Mexico.
Source: Wikipedia
Where it is found in the US
Recorded in 34 of 51 states and DC. Most records: Colorado, Texas, Michigan, Nebraska, New Mexico, Montana, Wisconsin, Indiana.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in United States; native in Canada. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
What plants does the alfalfa webworm moth damage?
Its caterpillars eat alfalfa and a range of other crops and weeds.
Source: Wikipedia
When are adult alfalfa webworm moths active?
Adults fly from March to October, and from May to early September in Alberta.
Source: Wikipedia
Where can I find alfalfa webworm moths?
They are found from Quebec to British Columbia and southward to Mexico.
Source: Wikipedia
Same family (Crambidae)
Box Tree MothCydalima perspectalisDamages trees, gardens or crops
Celery Leaftier MothUdea rubigalisDamages trees, gardens or crops
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/Loxostege_cereralis
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-24.