DEEP: Spotted Lanternfly

The Spotted Lanternfly and Connecticut
 
 
There is some concern that the spotted lanternfly (SLF) may be in Connecticut. The public should learn how to identify it and what to do should it arrive in the state.
 
 
 
{the spotted lanternfly}
Adult spotted lanternfly
Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org

 
Description:
The spotted lanternfly (Lycorma delicatula) adult is approximately one inch long and one-half inch wide with large and colorful wings. The front wings of the spotted lanternfly are light brown with black spots in the center. Their hind wings have contrasting patches of red and black with a white band in between. The legs and head are black; the abdomen is yellow with broad black bands.
 
{Adult spotted lanternfly}
 Adult spotted lanternfly showing the fore and hind wings
Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org
 
The three immature stages, called nymphs, are black with white spots. During the fourth and final nymphal stage, the developing insect adds red patches and small wing pads. Only the adult stage has wings.
 
            {Immature spotted lanternfly}                    {Late nymphs}
Immature spotted lanternfly (left) and fourth nymphal stage of immature spotted lanternfly (right)
Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org

The SLF is a planthopper of the family Fulgoridae, a family known for their bright colors and their pronounced snout-like head structure. SLF is considered to be native to China, India and Vietnam. It can walk, jump, or, as an adult, fly short distances. However it is a hitchhiking insect. It lays eggs on almost any surface, including vehicles, trailers, outdoor equipment, and patio furniture, and can be spread long distances when people move infested material.
 
Life Cycle:
SLF lays its eggs in the fall on smooth host plant surfaces and on non-host material. Bricks, stones, and dead plants can all serve as egg laying sites. Eggs are laid in masses of 30-50 eggs, with the individual eggs yellowish-brown in color. The egg mass itself is covered by a gray, waxy coating that is very indistinct. Eggs hatch in the spring and early summer, and nymphs begin feeding on a wide range of host plants by sucking sap from young stems and leaves. Adults appear in late July and tend to focus their feeding on tree of heaven (Ailanthus altissima) and grapevine (Vitus vinifera).
 
{the Life Cycle of the spotted lanternfly}
 The Life Cycle of the spotted lanternfly 
Colleen Witkowski, Penn State, extension.psu.edu
 
 
The SLF likely arrived in North America hidden on goods imported from Asia. The first detection of the spotted lanternfly in the United States was in Berks County, Pennsylvania in September 2014. SLF has now spread to 14 counties in southeastern PA with established populations in New Jersey (Warren, Mercer and Hunterdon Counties); two sites in Winchester, Virginia; and New Castle County in northern Delaware. USDA APHIS has not placed a federal quarantine in any state as of yet, but warns that the spotted lanternfly could survive year-round on the farmlands, forests or urban areas of most states in the northeast part of the country. The Commonwealth of Pennsylvania placed an Order of Quarantine and Treatment as of May 2018 and the NYS Department of Agriculture and Markets has established external quarantines on areas with infestation. Single SLF adults have been found in New York, Massachusetts, Maryland, and Connecticut; however no infestations have been reported in these states as of April 2019.
 
 
 
The SLF is an insect with a large and diverse host range. It feeds on about 60 genera of the trees and plants found in North America. In Connecticut, approximately 47% of the forest trees are considered as potentially susceptible to the SLF (See Tree List). Many of the fruit trees grown in Connecticut, such as apples, cherries, and peaches, are also considered to be vulnerable. Even if the insect does not kill the trees, it could destroy the value of the fruit. Grapes are likewise vulnerable. The impact on the agricultural industry of Connecticut could be devastating.
 
The degree of impact of the SLF on Connecticut's urban and rural forest trees is uncertain. It may turn out to be more of an annoyance with minor impact on forest health. However, there is the potential that it could cause much more significant damage.
 
 
Both nymphs and adults of the SLF feed by sucking sap from the stems and leaves of host plants. Depending upon the severity, this can weaken and damage the plant by reducing photosynthesis.
 
{Spotted lanternfly damage on a walnut tree (Juglans nigra L.)}
Spotted lanternfly damage on a walnut tree (Juglans nigra L.)
Eric R. Day, Virginia Polytechnic Institute and State University, Bugwood.org
 
Their feeding also creates a sticky, sugary residue called 'honeydew'. This honeydew attracts other insects and promotes the growth of a black mold called 'sooty mold', which can further damage the plant by blocking photosynthesis in the leaves of plants coated with the excrement. 
 
The honeydew itself is sticky, unsightly and hard to get rid of which is why SLF poses such a problem to fruit farmers. The presence of the honeydew can destroy the value of the crop.
 
The invasive tree of heaven is the preferred host plant for SLF, but it also feeds on a wide range of crops and plants, including grapes, apples, hops, walnuts and hardwood trees. The potential range of hosts is one of the reasons why SLF is of such great concern and may be so difficult to combat. Altogether, there are about 60 genera of trees and plants that SLF is known to attack in North America.
 
The following are among the genera at risk from SLF:
  • Almonds
  • Apples
  • Apricots
  • Beech
  • Black and paper birch
  • Black gum
  • Cherry trees and cherries
  • Dogwood
  • Elm
  • Grapes
  • Hops
  • Linden
  • Maple
  • Nectarines
  • Oak
  • Peaches
  • Pignut and shagbark hickory
  • Pine
  • Plums
  • Poplar
  • Sassafras
  • Serviceberry
  • Sycamore
  • Tulip poplar
  • Walnut
  • White ash
  • Willow
 
  • Direct Observation: SLFs group together in large numbers on hosts to feed, leading to large excretions of honeydew.
Depending on the time of year, a different life stage of the spotted lanternfly will be present.
{Calendar of spotted lanternfly Life Stage Presence}
PennState Extension
 
{Immature spotted lanternflies feeding}  
Immature spotted lanternflies feeding
Emelie Swackhamer, Penn State University, Bugwood.org

{Adult spotted lanternflies feeding}  
Adult spotted lanternflies feeding
(appear darker in color when not flying and showing their colorful hind wings)
Emelie Swackhamer, Penn State University, Bugwood.org
 
  • Oozing: Plants ooze or weep and have a fermented odor.  This comes from the wounds inflicted by the extensive feeding of the SLF.
{Weeping sap trail on tree}
 Weeping sap trail on tree
Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org
 
  • Honeydew Buildup: Look for the buildup of large amounts of a sticky fluid (honeydew) on plants and on the ground underneath infested plants (note - other insects such as aphids also excrete honeydew).
  • Sooty mold: Black sooty mold coats the leaves of the plants.
  • Egg mass: Gray, clay-like at first, turns brown and cracked.
{Egg mass covered in waxy coating}
Spotted lanternfly egg masses on tree
Richard Gardner, Bugwood.org
 
{Spotted lanternfly old hatched egg masses on a trunk}
     Spotted lanternfly old hatched egg masses on a trunk
Emelie Swackhamer, Penn State University, Bugwood.org
 
 
 
First, and most important if you think you may have found SLF, do not attempt to move any wood or other potentially infested material from the site. Instead, you can do one of two things:
 
Tree of heaven is the primary reproductive host of the spotted lanternfly. Places where large amounts of tree of heaven grow are potential points of establishment for SLF populations. To help the SLF surveying efforts, you can send detailed location information of stands of tree of heaven (10 or more) to CAES.StateEntomologist@ct.gov.
 
 
 
 
 
 
 
 
 
 
Content last updated October 2019