Over the past century, the forests of New Jersey have changed drastically. Having been altered by climate change, deer populations, and urban development, the local areas have had many challenges. Yet, even if not the most worrying of these, the spread of invasive species have become increasingly obvious within the past few decades.
One of these is the Emerald Ash-Borer (Agrilus planipennis), a small, green beetle with a metallic appearance. It is native to East-Asia and feeds predominantly on ash trees. In their natural environment, they have several predators to keep them in check, but North American environments have not adapted with the EAB in mind. After being found in the state for the first time in 2015 according to the Department of Agriculture, they have decimated local forests with nearly 10% of the total forested area in the state being susceptible.
Still, the Morris County Park Commission has created a lengthy response plan to reduce the impact of the Emerald Ash-Borer. Trunk injections of insecticides are being used, and at specific locations in the state stingless wasps have been released to control populations. These wasps are natural parasites of the Emerald Ash-Borer, and have been found to have minimal impact on native insect species.
Still, there is concern to be had over the effectiveness of these projects. The EAB has continued to spread throughout both the state and country, having been found in all NJ counties by 2020. In a statistic by the Cary Institute of Ecosystem Studies, any living ash trees are considered to be at high risk with over 99% of trees being killed in highly infested areas.
Information campaigns have been another essential tool against the spread of invasive species. Within the past few years, Rutgers University has created a program intended to teach grade school students of the effects and eradication of the Spotted Lanternfly (Lycorma delicatula), an invasive species of planthopper. They are another species indigenous to East Asia, and are one of the most well-known American invasives – they are large and brightly colored, making them difficult to miss. In 2021, the New Jersey Department of Agriculture created the Stomp it Out campaign, advising NJ residents to kill any lanternflies that they find.
Killing lanternflies directly may not be effective, however. Containing their populations and eliminating sources of food may be the key to eradicating them. Like many invasive species, Spotted Lanternflies can increase their range by hitchhiking on vehicles. Anyone travelling throughout or across states should pay attention to any hatched individuals or egg masses that have been attached to vehicles.
Mr. Kling, an Environmental Science teacher at WMC, points out that this is how many invasive species are initially introduced. “A lot of these invasive species were brought in unintentionally, “ Mr. Kling said. “We bought a box from Amazon or something, and it came from China, which is in a similar latitude to the United States. A lot of insect eggs or individuals may be released into the environment when somebody opens their box.” He doubts the effectiveness of killing individual lanternflies, considering how their populations thrive in densely forested areas. “I’ve never heard of an invasive insect being successfully eliminated using a manual technique like that, because they just reproduce so quickly. It only takes a few of them,” Mr. Kling stated. “The population of spotted lanternflies probably started with less than 10, and look at how they are now.” He believes that alternative methods such as the introduction of species-specific diseases or genetic modifications to reduce populations may be the key to eliminating the Spotted Lanternfly.
He also compares the effect of the emerald ash-borer on ash trees to the chestnut blight of the early 20th century, a fungal disease that wiped out over 3 billion chestnut trees across North America. The American Chestnut still exists, but it is critically endangered and functionally extinct. At times, it is very difficult to predict the future in an environmental context, but many question the future of the ash tree.
As for the Spotted Lanternfly, it seems unlikely that they will be eradicated from North America. Several species of mammals and insects within the United States have been found to predate on them, however, so it seems most likely that they, as well as other similarly widespread insects, will have to integrate into our ecosystems.
