Spotted lanternfly is unwelcome invader
Although issues surrounding immigrants dominated many of 2018’s headlines, it was a different kind of unwanted alien that arrived in Southeast Pennsylvania in 2018 and may dominate next year’s headlines as well.
We’re talking of course about that colorful pest, the spotted lanternfly.
It seemed like you couldn’t take two steps without being hit, literally, by one of these Asian pests with the rainbow wings until the first several frosts killed the adults.
First spotted in western Berks County in 2014, authorities have worked to contain the invasion of the insect which is native to China and Vietnam, but apparently jumped the Pacific on a pallet of stone delivered to Berks County at some point in the last few years.
Since its arrival, it has spread from one to 13 counties in Southeastern Pennsylvania and is making inroads into Virginia, Maryland, Delaware and New Jersey.
The lanternfly’s favorite food is the “tree of heaven,” which scientists call ailanthus altissima.
It is itself an invasive species, which is very hard to kill. It is also from Asia and although the spotted lanternfly prefers it, the bug is quickly developing a taste for native North American trees, including fruit trees, valuable hardwoods and grapevines.
When they feed, the lanternfly harms trees in two ways. The first is when it pierces the bark to feed on the nutrients in the layer beneath, robbing the tree of nutrients as well as leaving “weeping wounds” which can attract bees and ants, and also provides other insects or disease access to the tree’s interior.
The second way is what the insect excretes. Called “honeydew,” it is sweet and sticky, but it turns black into what Corondi called “sooty mold.” This smelly substance coats leaves and impedes photosynthesis.
The spotted lanternfly has seven stages of life, beginning with the gray egg masses. The masses which look like a mass of mud, usually vertically oriented on trees, rocks or even the siding of your house.
Each egg mass contains between 30 to 50 eggs.
They can be hard to spot because when fresh, they are a gray mass, usually laid on an equally gray surface and, as they dry out, they turn a dull gray.
Sadly, the cold does not kill the eggs, which will be mostly laid by late November and will hatch in the spring into small nymphs about the size of a tick.
They grow to about the size of a dime and take on the striking red and black coloring with white spots.
In this state, the lanternfly is actually susceptible to being sprayed with soapy water as the film from the soap can keep the bugs from breathing through their skin. But once they grow wings, this method seems to work less well.
Spotted lanternfly do not pose a risk to human health, but can affect forest hardwood products worth $16.7 billion in in Pennsylvania.
They like oak, maple and walnut and also affect apple and peach trees, an industry worth more than $119 million. In particular they pose a risk to Pennsylvania’s $944 million nursery and landscape industry.
The bugs travel the longest distances by hitching rides on our cars, trains and freighters.
That’s why officials urge people to carefully inspect their cars, trucks, trailers, campers and even firewood they are transporting to make sure they are not helping the pest to spread to other areas.
A variety of chemical weapons can be used. Several pesticides work, providing you can get close enough to use them.
A method called “hack and squirt” uses a type of pesticide called “systemics.” The lanternfly fighter uses a downward stroke to cut some holes in a “tree of heaven” infested with lanternfly and into these holes, apply specific pesticides designed for this function.
The tree with take up the pesticide, which the lanternfly will ingest as it feeds on the tree.
Eliminating all but one or two tree of heaven in a wooded area will force the lanternfly to focus on the remaining trees.
Using the systemic method then allows you to poison many more lanternfly with less poison, as well as eliminating more of the invasive trees.
Unfortunately, because the trees are dormant for the winter, this kind of assault must wait for spring.
The invasive spotted lantern fly is damaging trees in throughout southeast Pennsylvania.
This map shows sampling from 23014 through this year. the red dots indicated that so far, the spotted lanternfly remains concentrated in southeast Pennsylvania.
This slide shows how credit cards can be used to scrape spotted lanterfly egg masses off whatever they are attached to and put into a plastic bag to be destroyed. Each mass contains 30 to 50 eggs.