Public asked to check trees for invasive species in August

Throughout August, the Washington Invasive Species Council and the Washington Department of Natural Resources are asking the public to check trees in their communities for invasive insects.

August is the peak time of year that wood-boring insects are most often spotted outside of trees, according to a press release.

“State and federal agencies do a fantastic job at preventing the introduction of invasive species to the United States, but occasionally some slip through,” Justin Bush, executive coordinator of the Washington Invasive Species Council, said in the press release. “When a new invasive species is introduced, we need to know as quickly as possible so we can stop its spread.”

What’s at risk?

Invasive species are non-native organisms that include plants, animals and diseases, according to the press release. When introduced to a new environment, they do not have natural predators or diseases to keep their growth in check. Once established, they may damage the economy, environment, recreation and sometimes human health.

“Invasive insects impact our healthy forests and, in turn, destroy timber we manage that provides funding for schools, local services and our counties. The damage also increases fire risk and restricts recreation opportunities,” Commissioner of Public Lands Hilary Franz said in the press release. “Trees play an important role in our state economy and provide significant environmental benefits from clean air to habitat for wildlife and healthy waterways that support salmon and other fish. Tree loss from invasive species is something that we can avoid by stopping the spread of invasive insects. The public plays a key role in this effort as our eyes on the ground.”

What to look for

State officials urge the public to be especially aware of four invasive insects during their tree checks.

Invasive longhorned beetle: The larvae of this large beetle feeds on and in the wood of a tree. When the beetle becomes an adult, it emerges through holes that weaken the tree further. The beetle is extremely destructive to hardwood trees. It is not known to be found in Washington today, but it has been found multiple times in the past.

Emerald ash borer: This small, wood-boring beetle attacks and kills ash trees. The larvae burrow under the tree’s bark and eat the sapwood. Once damaged, the sapwood can’t transport water and nutrients, causing the leaves and tree to die gradually. While not yet known to be in Washington, it is spreading westward from the eastern United States.

Spotted lanternfly: This piercing, sucking insect feeds on sap from a variety of trees including apples, cherries, grapes, plums and walnut, and also on hops. While not yet found in Washington, the lanternfly has been intercepted in California on goods coming from the eastern United States.

Asian giant hornet: This hornet has been found in Whatcom County and kills honey bees. Though not typically aggressive to humans, it will attack anything that threatens its colony, which usually nest in the ground. It can sting multiple times and has powerful venom that can inflict serious injury or, in some cases, death.

People can participate by searching trees and reporting sightings.

“We’re asking people to take 10 minutes to search the trees in their yards and neighborhoods,” Bush said.

People who find a suspected invasive insect should take a picture and send the information on the Washington Invasives mobile app or on the website, https://invasivespecies.wa.gov/report-a-sighting/.

The photographs of the insect should show enough detail that an expert can verify it. People should include an object, such as a coin or pencil, next to the insect to indicate its size.

Because some species look like the invasive insects but aren't a problem, people are asked not to kill the suspected invader.

People can also take simple actions to prevent spread.

• People are advised to buy firewood where they will burn it, or gather it on site when permitted. When moving firewood people might also be moving invasive insects hiding there.

• When traveling locally or moving to a new area, people should check their bags and boxes to make sure they are insect free. Invasive insects, which can be in any life stage from larvae to adult, can tag along easily in bags and boxes and on items that have been stored outside or in garages.