At first glance, Lycorma delicatula looks like a beautiful butterfly, spotted and striped in black, white and red. But this insect, native to Asia, is attacking plants and crops in the United States, where authorities are working to contain its spread.
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“A good lycorma is a dead lycorma,” Amy Korman, an entomologist from the School of Agricultural Sciences at Pennsylvania State University, tells AFP bluntly.
The Lycorma delicatula (or Spotted Fulgor) was spotted in the United States in 2014 in the coastal area of Berks County, Pennsylvania. According to scientists who tracked him down, he arrived two years earlier aboard a cargo of stones from Asia.
It poses no threat to humans or animals, but has caused hundreds of millions of dollars in damage to the agricultural sector, although so far it has only spread to about fifteen eastern states. -United.
Photo Michael M. Santiago/Getty Images/AFP
A University of Pennsylvania study in 2020 estimated the annual cost at $554 million and the loss of nearly 5,000 jobs per year for this state alone, which has failed to contain the insect despite quarantines and numerous mobilizations.
“The Lycorma is a very good hitchhiker,” emphasizes Ms. Korman about this insect that, despite its spectacular wings, jumps more than flies and is easy to grab.
“It’s a very sneaky insect. It is thanks to us that it spreads. We are the ones who transport it around the country, especially its eggs,” she explains.
The eggs – 30 to 50 aligned brownish grains of rice – are laid on flat surfaces (logs, rocks, cars) and have “survived very harsh winters.”
As an adult, the Lycorma sucks up the plant sap with a proboscis, depriving it of this vital nutrient. When multiple specimens feed on the same plant, the number decreases.
Photo Michael M. Santiago/Getty Images/AFP
Loves grapes
This insect, with an abdomen 25 mm long and 15 mm wide, feeds on more than 70 species of ornamental plants, fruit and shell trees, and forestry. He has a particular appetite for vines.
Scientists have observed swarms of dozens or even hundreds of individuals on a single vine.
Vineyards in Pennsylvania and Maryland lost half their production due to plant death and reduced yield of those that survived the cure.
“We lost a thousand vines,” Michael Fiore, owner of a vineyard in Maryland, northeast of Washington, told AFP, which will be raided in 2022.
“They’ve sucked up all the energy, they’re like vampires,” he says, dismayed, admitting that he expects to lose half of his harvest again this year. “2022 was bad, 2023 is just as bad.”
“It will take some time to rebuild the vines,” he admits.
The flora is also affected by the insect’s feces, a honeydew, which causes a mold called sooty mold, which, when it covers the leaves, prevents photosynthesis.
Photo Michael M. Santiago/Getty Images/AFP
Several states have tasked scientists with finding a means to eradicate it, which is a real race against time as models predict its arrival on the West Coast around 2027-2030.
Huge, renowned vineyards abound in California, not to mention the almond orchards or even orchards of Oregon further north. Canada is also worried.
California’s wine industry generates $170.5 billion for the American economy and employs 1.1 million people, according to the Wine Institute, its representative body.
The U.S. Department of Agriculture unveiled a five-year strategy to investigate and combat Lycorma in June.
“We cannot understand his behavior,” regrets Matthew Travis, who is responsible for the fight against “SLF” in the ministry – “spotted lanternflies”. “It’s a real challenge for us.”
“We still don’t know much, especially about population changes from one year to the next and their distribution,” he emphasizes, pointing out that study visits have been carried out in Asia, “but they have never seen the big phenomena that we experience.
This makes it difficult to estimate the long-term financial consequences.
On the ground, residents organize patrols to kill them – they are not very mobile, you can easily crush them with your foot, but their size makes things quite unpleasant.
Westchester County, near New York, uses sniffer dogs for eggs and powerful “Ghostbusters”-style vacuum cleaners for nymphs and adults.
Some poison the sap of the glandular ailanthus, an invasive tree also native to Asia that is very popular with Lycorma and has no real predator in the Americas.