Invasive Species Alert

​Spotted Lanternfly

The spotted lanternfly (SLF) was detected in Virginia in January 2018. It is an invasive planthopper that was discovered in Pennsylvania in 2014. In Pennsylvania and its native range, SLF is a pest of grapes, peaches, hops, and apples. It is commonly associated with tree-of-heaven, Ailanthus altissima. It has the potential to be a serious pest of agriculture and home gardens in Virginia.


​Signs of Infestation

Signs and symptoms of the spotted lanterfly include:
  • muddy-grey egg masses on or around host trees until eggs hatch in late spring; 
  • dark streaks or sap flowing down the bark of the tree resulting from the spotted lanternfly piercing the bark to access phloem and sap in order to feed;
  • honeydew secretions (insect secretions) at the base of a host tree that can become covered in a sooty-coloured mold; and,  
  • increased bee and wasp activity due to exposed sap and honeydew adult insects congregating on host trees (especially Ailanthus altissima) in the fall.

Do you think you’ve identified a spotted lanternfly?

If you think that you have found a spotted lanternfly, you can take a specimen to your local Virginia Cooperative Extension office (

To learn how to identify spotted lanternfly, visit Virginia Cooperative Extension’s Spotted Lanternfly page:

Emerald Ash Borer

An infestation of this non-native beetle was confirmed in 2015 in neighboring Fairfax County. The Emerald Ash Borer was first discovered killing ash trees in Michigan in the late 1990s.

Accidentally introduced into North America from Asia, the Emerald Ash Borer has killed tens of millions of ash trees and caused billions of dollars of damage to the forestry industry. This is only the second time that this pest has been found in the Northern Virginia area since a minor outbreak was contained in 2003.
Emerald Ash Borer

Types of Ash Trees

There are many species of ash trees and the emerald ash borer will attack them all; the result is almost always fatal. Green and White Ash trees are commonly found in this area. Please visit the Dendrology at Virginia Tech Web site for more information on how to identify ash trees.

Signs of Infestation

Early detection is the best strategy for management of the pest. Signs of emerald ash borer activity include dieback in the top 3rd of the tree canopy, sprouts growing from roots and trunk, bark splitting and D-shaped exit holes. To learn more about emerald ash borer please visit the United States Department of Agriculture (USDA) Forest Service website.

The emerald ash borer does not generally spread great distances on its own. It is mainly spread when various ash articles (firewood, wood chips, nursery stock, etc.) are transported from infested areas to uninfected areas.

Citizen Reports

Residents are asked to report any signs of declining or dying ash trees by contacting the Department of Public Works at 703-248-5350 (TTY 711) or
Healthy Ash Tree
Ash Trunk Growth
Canopy Dieback