2019 Trapping Results
Total spongy moths caught to date: 14
| Date | County | Location | Molecular Diagnostics | Name of Moth | ||
|---|---|---|---|---|---|---|
| FS1 | Mitochondrial | Scientific | Common | |||
| 7/25/2019 | Snohomish | Woodway | Asian | A1 | Lymantria umbrosa | Hokkaido spongy moth |
| 7/25/2019 | Klickitat | Goldendale | Heterozygous | North American | Lymantria dispar dispar | European spongy moth |
| 7/25/2019 | Klickitat | Goldendale | Heterozygous | North American | Lymantria dispar dispar | European spongy moth |
| 8/5/2019 | Clark | La Center | North American | North American | Lymantria dispar dispar | European spongy moth |
| 8/7/2019 | Whatcom | Lynden | Heterozygous | North American | Lymantria dispar dispar | European spongy moth |
| 8/19/2019 | Pierce | Tacoma | North American | North American | Lymantria dispar dispar | European spongy moth |
| 8/19/2019 | Clark | Ridgefield | North American | North American | Lymantria dispar dispar | European spongy moth |
| 8/26/2019 | King | Shoreline | North American | North American | Lymantria dispar dispar | European spongy moth |
| 9/11/2019 | Snohomish | Boulevard Bluffs | North American | A1 | Lymantria dispar dispar | European spongy moth |
| 9/11/2019 | Snohomish | Boulevard Bluffs | Heterozygous | A1 | Lymantria dispar dispar | European spongy moth |
| 9/16/2019 | Snohomish | Boulevard Bluffs | Heterozygous | A1 | Lymantria dispar dispar | European spongy moth |
| 9/24/2019 | Pierce | Anderson Island | North American | North American | Lymantria dispar dispar | European spongy moth |
| 9/30/2019 | Pacific | Illwaco | North American | North American | Lymantria dispar dispar | European spongy moth |
| 9/30/2019 | Pacific | Illwaco | North American | North American | Lymantria dispar dispar | European spongy moth |
Discussion of Survey Results
In 2019, the Washington State Department of Agriculture (WSDA) deployed nearly 23,000 spongy moth detection traps in Washington State for European spongy moth and Asian spongy moth. Both European and Asian spongy moths are a great threat to Washington State’s forests and urban landscapes; however, the risk of rapid spread and severity of damage is higher with the Asian spongy moth species due to female flight capability and a wider range of host trees which includes conifers. European spongy moth species have a smaller host range and the females are unable to fly which minimizes the potential for natural spread.
Fourteen (14) adult male spongy moths were collected and have undergone DNA analysis for determination of either Asian or European genotypes. Molecular diagnostics has identified one moth collected in a trap in Snohomish County as Lymantria umbrosa, Hokkaido spongy moth; this is the first detection of this species in the United States. Hokkaido spongy moth is considered an Asian spongy moth and has the same feeding and female flight behavior as Asian spongy moth.
DNA analysis found 2 moths that were collected in Snohomish County to be heterozygous; this means they have both North American and Asian DNA. Heterozygous species are of greater concern because female moths produced from this population may exhibit Asian traits and may be flight capable. The presence of flight capable females might increase the potential rate of spread and complicate our ability to detect and eradicate isolated populations.
Fourteen (14) adult male spongy moths were collected and have undergone DNA analysis for determination of either Asian or European genotypes. Molecular diagnostics has identified one moth collected in a trap in Snohomish County as Lymantria umbrosa, Hokkaido spongy moth; this is the first detection of this species in the United States. Hokkaido spongy moth is considered an Asian spongy moth and has the same feeding and female flight behavior as Asian spongy moth.
DNA analysis found 2 moths that were collected in Snohomish County to be heterozygous; this means they have both North American and Asian DNA. Heterozygous species are of greater concern because female moths produced from this population may exhibit Asian traits and may be flight capable. The presence of flight capable females might increase the potential rate of spread and complicate our ability to detect and eradicate isolated populations.