This is a large (FW length 24-27mm), very common and highly variable Noctuid moth which is found in a wide variety of habitats. Despite its variability it is a distinctive moth with a long and narrow forewing in some shade of brown, and a yellow/orange hindwing sharply margined by a thick black line. It also has 2 dark dots (often fused) where the subterminal line meets the costa near the apex of the wing. The only moth it is likely to be confused with is Noctua comes, which is smaller with stubbier wings, usually lacks the subterminal dots, and has a black discal spot on the orange/yellow hindwing.
This Eurasian native was accidentally introduced to North America on the East Coast in 1979, and by 2011 had spread throughout the PNW. It is very adaptive and can be found in every habitat in our region, sometimes erupting in massive outbreaks which do major agricultural harm. The larvae are generalists feeding on almost every imaginable type of grass and herbaceous vegetation. Adults fly from May to October, and appear able to migrate long distances, no doubt accounting for this species’ rapid expansion across the continent.
Size– FW length 24-27mm
Range– Region wide
Eats– Larvae feed on most grasses and herbaceous vegetation
Flight Season– May to October
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