The spotted lanternfly (Lycorma delicatula) is an invasive insect from Asia, first detected in the United States in Pennsylvania in 2014. It has since spread rapidly, posing a significant threat to agricultural industries and native ecosystems.
How Spotted Lanternflies Harm Native Plants
Spotted lanternflies harm plants by extracting large quantities of sap from stems, trunks, and branches using piercing-sucking mouthparts. This depletes the plant’s stored sugars and nutrients, stressing it and reducing its ability to photosynthesize, leading to weakened health.
As they feed, spotted lanternflies excrete sticky honeydew. This honeydew accumulates on plant surfaces, providing a growth medium for black sooty mold. The sooty mold covers leaves, blocking sunlight and hindering photosynthesis. This dual impact weakens the plant, making it more susceptible to environmental stressors, diseases, and pests.
Native Trees and Plants at Risk
While the invasive tree of heaven (Ailanthus altissima) is a preferred host, spotted lanternflies feed on a wide range of native trees and plants, with a host list exceeding 70 species. Native maples, including silver and red maple, are particularly vulnerable, especially their saplings. Oaks are also impacted by their feeding.
Black walnut trees are significantly affected. Birches and black cherry are additional native species that lanternflies feed upon. The combined stress from sap feeding and sooty mold can lead to branch dieback, reduced growth, and a decline in the health of these native species. While some hardwoods may recover over time, initial impacts can be substantial, especially on young trees.
Broader Ecological Consequences
The decline of native trees and plants due to spotted lanternfly activity has broader implications for the entire ecosystem. As these plants weaken or die, native wildlife that relies on them for food, shelter, or breeding sites can be negatively affected. This includes various insects, birds, and mammals that form interconnected food webs.
The weakening or potential loss of keystone native species can alter the overall forest structure and reduce biodiversity. Additionally, the abundant honeydew produced by the lanternflies attracts other insects, such as ants, bees, and wasps, which can disrupt the natural balance of beneficial insect populations, including pollinators. This outcompetition of native plants and the subsequent disruption of ecological relationships can lead to shifts in plant communities and a reduction in the overall health and resilience of affected ecosystems.