As Pennsylvanians grow more aware of the seriousness of the ecological threat posed by the invasive spotted lanternfly, DCNR is taking some steps to help respond.
DCNR is not leading state efforts to combat the spotted lanternfly, as the insect’s reputation for destroying agricultural products, like grapes, drew a strong response of action and information from the Pennsylvania Department of Agriculture.
DCNR’s Bureau of Forestry is serving in a more supportive, collaborative fashion, leveraging resources and skills related to forestry work to help in the fight against this invasive pest.
The Division of Forest Health within DCNR’s Bureau of Forestry routinely performs aerial surveys of Pennsylvania’s forests (PDF), checking for tree dieback, mortality, defoliation, and foliage discoloration.
Aerial Surveys Help in the Fight Against Spotted Lanternfly
The Division of Forest Health used traditional aerial surveying methods to generate an Ailanthus map.
Ailanthus, the genus name of a common invasive tree called “tree of heaven,” happens to be a preferred food and host in the life cycle of the spotted lanternfly.
If we know the location of colonies of tree of heaven, then theoretically, we should be able to find colonies of spotted lanternfly and contain them – helping to reduce their impact.
Tree of heaven has a distinctive look from the air. Female Ailanthus trees form heavy clusters of whitish seeds, highly visible from above.
Helicopter surveys in a grid pattern in areas in and surrounding spotted lanternfly quarantine zones helped develop a map of the tree of heaven.
This information is being shared with the Pennsylvania Department of Agriculture, which will determine how it is used in the fight against the spotted lanternfly.
- Factors the department must confront include:
- Number and density of Ailanthus colonies
- How many (if any) to eradicate
- Which ones to use as “trap trees”
Site accessibility and landowner permission to enter property are also important factors.
State Forests are Preparing to Fight Spotted Lanternfly
Scientists in DCNR’s Division of Forest Health have advised forest district managers in Pennsylvania state forests adjacent to the spotted lanternfly outbreak -- mostly concentrated at this time in southeastern Pennsylvania -- to inventory tree of heaven colonies as soon as possible.
This will enable a swifter, more effective response if/when the spotted lanternfly arrives in counties to the north and west of this invasive bug’s range. Pennsylvania has 20 state forest districts.
One Invasive Species May Help in the Fight Against Another
In what some scientists might deem a form of ecological poetic justice, a terrible invasive species -- tree of heaven -- may just contribute to the control of another (and perhaps more detrimental) invasive species -- the spotted lanternfly.
One thing is certain, DCNR’s Ailanthus map will be an important tool in the Pennsylvania Department of Agriculture’s strategy to deal with the growing specter of a rapidly expanding population of this invasive pest.