Bug FAQMiller, Blue-Gray, and Cottonwood Daggers
Acronicta vulpina · Order: Lepidoptera · Family: Noctuidae
Also called: Miller Dagger, Vulpina Dagger, Vulpina Dagger Moth
The Miller, Blue-Gray, and Cottonwood Dagger (Acronicta vulpina) is a moth in the Noctuidae family. Its wingspan measures about 40 to 47 mm and adults fly from May through July. It lives across North America from the Atlantic coast to central British Columbia and south to Colorado.
Source: Wikipedia
How to recognize it
Acronicta vulpina is the scientific name for the Miller, Blue-Gray, and Cottonwood Dagger moth.
Source: Wikipedia
Size
The moth’s wingspan ranges from 40 to 47 mm.
Source: Wikipedia
What it eats
The caterpillars feed on trembling aspen, paper birch, balsam poplar, speckled alder, and various willow species.
Source: Wikipedia
Life cycle
Adults are on the wing from May to July, depending on location.
Source: Wikipedia
When you see it
The flight season for adults spans May through July.
Source: Wikipedia
Where it comes from
Its native range covers much of North America, including eastern Canada and the United States.
Source: Wikipedia
Where it is found in the US
Recorded in 19 of 51 states and DC. Most records: Maine, Minnesota, Michigan, Colorado, Montana, New Hampshire, Wyoming, Vermont.
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
When can I see the adult moths?
Adults are active from May to July, varying with location.
Source: Wikipedia
What trees do the caterpillars eat?
The larvae feed on trembling aspen, paper birch, balsam poplar, speckled alder, and willow species.
Source: Wikipedia
Where is this moth found?
It occurs across North America from the Atlantic coast to central British Columbia and south to Colorado.
Source: Wikipedia
Same family (Noctuidae)
Ipsilon Dart MothAgrotis ipsilonDamages trees, gardens or crops
Fall Armyworm MothSpodoptera frugiperdaDamages trees, gardens or crops
Army Cutworm MothEuxoa auxiliarisDamages trees, gardens or crops
Large Yellow UnderwingNoctua pronubaDamages trees, gardens or crops
Silver ΥAutographa gamma
American DaggerAcronicta americanaCan irritate skinSources
- Wikipedia: https://en.wikipedia.org/wiki/Acronicta_vulpina
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-27 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-27.