What is a Spotted Lanternfly?

Spotted Lanternfly

The Lycorma delicatula, more commonly known as the spotted lanternfly, is an invasive species that was first discovered in the United States in Pennsylvania in 2014. An invasive species is a species that has been artificially introduced into an environment that it is not naturally found in. Invasive species can cause severe damage to the environment, which can in turn cause economic damage and create a public health issue. The spotted lanternfly is not yet found throughout the United States, but has been found in 12 states, all above the Mason-Dixon line. Regardless, the spotted lanternfly may eventually be found in St. Louis, so it is important to be familiar with it, in order to prevent harm.

What is the Spotted Lanternfly?

The spotted lanternfly is native to China, but has spread to Japan, South Korea, and the United States. Commonly described as a planthopper, spotted lanternflies look very similar to leaves in the environment, so they may be difficult to spot. Planthoppers are also known to “hop” from plant to plant, similar to the movements of a grasshopper. Even though they are a winged insect, they rarely fly, but rather use this hopping mechanism to hop and glide from plant to plant. Their wings aid in their ability to quickly and efficiently move from plant to plant, enabling them to spread quickly.

Spotted lanternflies are small insects, found to be about one inch long and one-half inch wide. Females tend to be larger than males, especially when mated. These insects have a black head and neutral-colored wings with approximately 20 spots on them, hence where they get their name! When their wings expand while resting or flying, you can see a red underside of the hind wings. Their abdomen is yellow.

The life cycle of the spotted lanternfly begins when the nymphs hatch from eggs, typically during the Spring months, around late April to early May. The coloring of these nymphs are originally black with white spots, but as they transition to adulthood, they develop wings and their coloring becomes more grey. Because they don’t have wings, nymphs tend to favor herbaceous plants and do not spread easily. 

The Spotted Lanternfly as an Invasive Species

As mentioned previously, the spotted lanternfly is an invasive species in the United States, meaning it is not naturally found here. Originally from China, the spotted lanternfly may also be found in Taiwan, Vietnam, and India, though they are not considered invasive species in these three countries. In 2006, the spotted lanternfly was found in South Korea, and it was declared an invasive species in 2007. There are no natural predators for the spotted lanternfly in South Korea. In 2009, the spotted lanternfly was found in Japan, and in 2014 it was found in Pennsylvania for the first time. Japan and the United States also do not have natural predators for the spotted lanternfly, allowing the insect to flourish. The most common method of spreading as an invasive species is the eggs traveling on imported objects that have smooth surfaces, such as bark and stone. The spotted lanternfly’s natural predator are parasitic wasps, which are not found in South Korea, Japan, or the United States.

In the United States, the spotted lanternfly directly affects the grape, fruit tree, and logging industries. Pennsylvania State University estimates over $500 million in damages due to the spotted lanternfly, including job losses. As a result, many states have instituted quarantines on objects imported, including firewood, outdoor chairs, trucks, and other vehicles. The spotted lanternfly has almost spread to Michigan, Kansas, Oregon, and California, but quarantines were able to prevent the spread.

Why are Spotted Lanternflies Dangerous?

The good news is that the spotted lanternfly is not dangerous to people! These insects do not bite humans. However, they are dangerous for plant life. Spotted lanternflies eat a lot of plants, specifically plant sap. Spotted lanternflies have a strong preference for maple, black walnut, birch, and willow trees. The damage caused to these trees can lead to plant death, which severely affects the flow of the ecosystem and the U.S. economy. 

Furthermore, the extraction of sap attracts other insects, which is not natural to the cycle of the ecosystem. Bees and wasps are attracted to the sap, specifically the honeydew, that is extracted from the trees. The extracted honeydew also grows mold, which can further damage plant life.

What Should I Do If I See a Spotted Lanternfly?

Since the spotted lanternfly hasn’t been found in St. Louis yet, it is vital that you report a sighting! Early reporting can help mitigate the spread of this invasive species, which will protect the Missouri and St. Louis economy. Early detection and containment will prevent the destruction that spotted lanternflies cause to the ecosystem and economy, as we have seen in Pennsylvania, so we won’t need to launch a huge pest control effort to stop them.

The best way to prevent the spread of the spotted lanternfly is to kill off the eggs when they are first laid, typically in the late Fall. You can scrape off the eggs and double bag them, pouring some alcohol or hand sanitizer into the bag before tying it off and disposing of them. Additionally, the sap of the  Ailanthus altissima is needed for the spotted lanternfly to lay its eggs, so removing these trees can also prevent the spread. 

Professionally, the experts can use infrared technology to detect spotted lanternflies, as they emit infrared wavelengths while feeding. There are also dogs that are trained to detect spotted lanternflies. The U.S. government has also considered the implementation and controlled introduction of certain wasps that can become natural predators for the spotted lanternfly, but more research is required, in case these wasps become another invasive species in the United States.