State agencies are asking the public to report an invasive tree called tree-of-heaven throughout October to help prevent the introduction of a harmful insect, the spotted lanternfly.
The Washington Invasive Species Council, Washington State Department of Agriculture (WSDA), Washington State Noxious Weed Control Board and other agencies are asking the public to look in their communities for tree-of-heaven and spotted lanternfly and report sightings on the Washington Invasives mobile app or the council’s online reporting Web page.
“We need your help to find and report tree-of-heaven, which is known to be in at least 18 of Washington’s 39 counties,” said Justin Bush, executive coordinator of the Washington Invasive Species Council. “While we know the trees are relatively widespread, we don’t know exactly where they are or how large the patches are. We hope the public can help us better understand the distribution of tree-of-heaven as quickly as possible because of its relation to the spotted lanternfly.”
State officials hope that by locating tree-of-heaven, they can stop the more dangerous spotted lanternfly, which prefers tree-of-heaven for portions of its life. The spotted lanternfly, first detected in the United States in Pennsylvania in 2014, has spread to other states including Delaware, Maryland, New Jersey, New York and Virginia, despite federal and state quarantines and control activities. Dead, but no living spotted lanternfly also have been found in California and Oregon as hitchhikers on goods from the eastern United States.
“Spotted lanternfly looks like it could be one of the most harmful pests in our generation,” said Sven-Erik Spichiger, managing entomologist for WSDA. “Washington has a wide range of suitable habitat and a wide range of hosts it can feed on, such as grapes and hops.”
In addition to those crops, spotted lanternfly can damage other agricultural commodities and urban and wildland trees such as maple, oak, pine and willow. This invasive pest secretes a sugar-rich, sticky liquid called honeydew causing sooty mold to grow and cover vegetation. Scientists estimate the spotted lanternfly could cost the state agricultural industry more than $3 billion annually. The insect also could cause irreversible damage to the environment, including trees shading streams, urban street trees and forests.
Besides being a preferred host for spotted lanternfly, tree-of-heaven is a problem because it grows fast and forms thickets that outcompete native plants. It also changes the chemistry of soil, which prevents or harms neighboring plants.
Tree-of-heaven can grow up to 60 feet tall, loses its leaves in the winter and smells like rancid peanut butter or popcorn.
Spotted lanternflies are about 1 inch long, with distinct black spots on light brown or gray wings. Their hind wings have a distinct red and black pattern.
“Spotted lanternfly adults are very distinctive with few native look-a-likes,” Spichiger said. “In other states, public reports have been more than 90 percent accurate. If you spot something that looks like spotted lanternfly, there is a good chance that you are finding a new invasive species that risks billions annually to Washington.”
When reporting sightings, the public should include photographs that show enough detail for experts to identify the tree. A photo showing the leaf and leaflets is most helpful. The public also should include a description of the size of the stand of trees, such as whether there is a single tree or a group of trees that are the size of a motorcycle, a car, a school bus or multiple school buses.
Help Develop a Plan to Protect Washington
Tree locations will be used by officials to develop a state strategy to address tree-of-heaven in high priority areas near transportation hubs and agricultural areas, and to guide surveys for spotted lanternfly. The council and partnering agencies are beginning a process to develop a spotted lanternfly action plan, which will strengthen state prevention efforts and ready agencies for rapid response if spotted lanternfly is found.
While considered an invasive species and legally classified as a Class C noxious weed, most county noxious weed control boards currently are not requiring removal of tree-of-heaven. Landowners seeking information on how to remove tree-of-heaven or seeking non-invasive alternatives for landscapes should contact the Washington Invasive Species Council or join a November 1 Webinar. Those reporting tree-of-heaven to the council will receive information on these topics.
Government agencies and researchers are hosting a November 1 Webinar to summarize census outcomes and share more information on the risk to the economy and environment. Visit the Webinar Web page to register.
“We need your help to protect all we know and love about Washington,” Bush said. “By taking a few minutes to seek and report these two harmful invasive species in your community, you are playing a very important role in protecting our state.”
Photographs and Maps
- Tree-of-Heaven (Credit: Washington State Noxious Weed Control Board)
- Tree-of-Heaven Bark (Credit: Washington State Noxious Weed Control Board)
- Tree-of-Heaven Leaf and Leaflets (Credit: Washington State Noxious Weed Control Board)
- Tree-of-Heaven Seed Clusters (Credit: Washington State Noxious Weed Control Board)
- Tree of Heaven Leaf Scar (Credit: Jan Samanek, Phytosanitary Administration, Bugwood.org)
- Adult Spotted Lanternfly (Credit: Pennsylvania Department of Agriculture)
- Spotted Lanternfly Egg Masses (Credit: Pennsylvania Department of Agriculture)
- Spotted Lanternfly Egg Mass Close Up (Credit: Pennsylvania Department of Agriculture)
- Tree-of-Heaven Distribution Map (Credit: Washington State Department of Agriculture)
- Spotted Lanternfly Suitable Habitats in Washington State Map (Tewodros T Wakie, Lisa G Neven, Wee L Yee, Zhaozhi Lu, The Establishment Risk of Lycorma delicatula (Hemiptera: Fulgoridae) in the United States and Globally, Journal of Economic Entomology, Volume 113, Issue 1, February 2020, Pages 306–314,