In Harford and Baltimore Counties we are seeing more Spotted Lanternflies present on homeowners’ properties. They are destructive, invasive species that are harmful to fruit and produce crops, and they’re spreading like a wildfire. They are not dangerous to humans or pets (in the sense that they do not sting or bite) but they should be taken seriously and proactively managed to reduce their negative impact. 

The Lifecycle of Spotted Lanternflies

The Spotted Lanternfly follows a one-generation lifecycle. They are born in early spring and develop through the summer, reaching the adult phase around August. They lay eggs in September and the fall season, and then die by the start of winter. The egg masses can be found on trees through winter and will hatch in spring. Note, be on the lookout for egg masses, as they should be scraped off and destroyed.

Host Trees Preferred by Spotted Lanternfly

The Tree of Heaven appears to be the most preferred host tree for breeding. The Tree of Heaven is an invasive, nuisance species originally from China. It grows quickly in disturbed areas on the side of the road and field edges. But Spotted Lanternfly will also reproduce on oaks and willows. In addition to trees, egg masses can be found on stationary objects around the house, such as siding, lawn furniture, vehicles, large stones, and structures. 

Tree Damage by Spotted Lanternfly

Spotted Lanternflies are attracted to fruit trees such as peach, apple, and grapes, plus walnuts, oaks and pines. They feed on the sap from the tree’s stems, trunks, and leaves. They emit a sugary, sticky substance called honeydew which sticks to the leaves and fruits, attracting other pests to the tree. Sooty mold will grow in their honeydew which contaminates fruit and adversely impacts and weakens the tree by reducing photosynthesis. 

Note any trees that seem to be crowded with any of the development stages of Spotted Lanternfly. Keep an eye out for the honeydew substance stuck on the leaves or other parts of the tree. It is unlikely a healthy tree will die from Spotted Lanternfly impacts but it will be significantly stressed. Vulnerable or weakened trees could be killed if they undergo severe damage. Be sure to provide sufficient mulching, watering, and perhaps supplemental fertilizer for impacted trees.


Measures to Stop and Reduce Spotted Lanternfly Damage

  1. Eliminate the host tree, Tree of Heaven from your property. Note it can easily be mistaken for a walnut tree or the native sumac, so tree identification is essential. Plant ID mobile apps such as PictureThis, among others can be helpful in distinguishing these plants.
  2. Scrape egg masses from trees and structures. They will be present in fall and winter and look like a patch of mud on the tree. They can be crushed or saturated in alcohol. Be sure to clean any boots or gloves used in crushing eggs to avoid inadvertently transferring eggs elsewhere.
  3. Insecticidal soap and neem oil are safe products to use on the insects themselves and the trees they congregate on. There are additional EPA-registered insecticides, which must be applied with strict timing and application requirements. All pesticides should be applied according to the label’s specifications.


If you need help managing the trees on your property or would like a tree assessment, kindly call our office to schedule an appointment. We provide full-service tree maintenance, removal and trimming in Glen Arm, Baldwin, Hydes, Fallston, Phoenix, Jacksonville, and the surrounding areas.