Spilosoma virginica (Virginian tiger moth) - wing markings Spilosoma virginica
(SPIL-oh-so-mah  ver-GIN-eh-kah)
Family: Erebidae            Subfamily: Arctiidae
Common name: yellow woolly bear; Virginian tiger moth
Host plant(s): range of low-growing, herbaceous plants
Adult size: wingspan: 1.3 – 2.0 in (3.2-5.2 cm)
Larval length: up to 2.0 in (5.0 cm)
Flight time: May through August

Type: minimal pest  

Life cycle:
            Generations per year: 2 to 3
            Egg: unknown
            Larva: unknown
            Pupa: unknown
            Adult: unknown

Spilosoma virginica (Virginian tiger moth) - side viewDescription: A medium-sized moth with white head, thorax, abdomen, and wings. The forewing has two black dots; the hindwing has several black dots, mostly located in a row in the  marginal area. Anterior legs are marked with yellow and black; remaining legs are white and black. The white abdomen is characteristically marked with yellow-orange and black dots arranged symmetrically.

yellow woolly bear caterpillar (Spilosoma virginica)Larva is woolly-looking, covered densely with long yellow and white hairs.

Adult moths begin to appear in late spring…typically May. After mating, females will lay 20 – 100 eggs grouped in a single layer on the underside of a leaf. When larvae hatch, they stay together for a brief period, feeding, and then disperse singly to other plants. Larvae defoliate host plant by skeletonizing its leaves, but usually does not harm the plant. Most larval damage occurs in the last generation as fall approaches. This generation will overwinter in the pupa stage. There are two to three generations per year.


Spilosoma virginica moth (Virginian tiger moth) - front viewSpecial Notes: Native throughout the temperate regions of North America. Here in the Pacific Northwest, it is generally found at low elevations from the northern parts of central British Columbia to central California.


Remedial Actions: None needed. Not a serious pest.


Re-posted on July 17, 2018