The spotted lanternfly (Lycorma delicatula) is an invasive insect first found in Pennsylvania in 2014. It has since spread rapidly, threatening crops, trees, and ecosystems. How They Harm Plants Lanternflies pierce plants to suck sap, weakening them and making them vulnerable to disease. They also excrete honeydew, which promotes black sooty mold that blocks sunlight… The spotted lanternfly (Lycorma delicatula)...