Small but mighty, the spongy moth can do some major damage to trees and shrubs not only in Washington state but across the country.

The Washington State Department of Agriculture’s spongy moth trappers had a busy season this year, trapping 103 spongy moths compared to last year’s thirty moths caught statewide and only six in 2021. 

The spongy moths were caught as part of the WSDA Pest Program’s regular summer moth survey program, with more than 20,000 traps placed around the state this year. Of the moths trapped, 81 were in Thurston County, with 77 trapped near Steamboat Island Road, making that the most moths trapped in one area in more than 30 years. Other counties with spongy moth catches include Pierce, Skagit, King, San Juan and Snohomish. 

The state department of ag has successfully prevented spongy moth from establishing in the state since 1974. Each year, the state has new introductions of the invasive pest from people moving from the Eastern U.S. where 20 states are permanently infested with the moth or, more rarely, through the ports.

Spongy moth is an extremely destructive pest that threatens entire forests, parks and neighborhood trees and shrubs. The moths can defoliate acres of trees during outbreaks, which can result in the death of millions of trees and the destruction of native habitat for countless species. During an outbreak in eastern states in 2016, the damage was so extensive it could be seen on NASA satellites.

More information is available about spongy moths, the WSDA trapping and eradication programs by visiting the department's website.

Source: Washington State Department of Agriculture

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