Invasive insect that kills grapes could reach California wine country by 2027

The spotted lantern, an invasive insect that can kill vines and damage other crops, has a chance to reach California’s wine counties for the first time in five years, according to a new analysis researchers from North Carolina State University.

In the study published in Communications Biologythe researchers used a computer simulation tool to predict when the spotted lanternfly would spread, Lycorma delicatula, across the United States if efforts to control its spread are halted. They predicted that there is a high probability that the insect will spread to North Carolina by 2027, and a chance that the insect will first reach California wine counties in the same year.

“This is a big concern for winegrowers; this could lead to billions of dollars in losses in the agricultural sector,” said the study’s lead author, Chris Jones, a researcher at the North Carolina State Center for Geospatial Analysis. “With this study, we have a baseline that we can use to assess the effect of different management strategies.”

The dappled lantern originates from Asia. It was first identified in the United States in Pennsylvania in 2014. Since then, it has spread to at least 11 other states. The invasive insect may damage or destroy commercially valuable crops such as grapes, apples, almonds, walnuts, cherries, hops and peaches, as well as certain trees. It kills plants by feeding directly on them and can also damage them by leaving a residue called “honeydew” which promotes mold growth. California, which produces 82% of the country’s grapes, has been identified along with Washington state as a “highly suitable” climate for the spotted lanternfly.

“It’s hard to say in advance exactly what impact the spotted lanternfly will have on West Coast grape-growing regions because we only have data from cold-producing regions,” Jones said. . “In Pennsylvania, we have seen vineyard losses from the double whammy of cold weather and mottled lanterns feeding on the vines. But we know growers can also experience losses from mold growth alone.”

To predict the insect’s spread, the researchers used a computer simulation tool known as “PoPS,” or the Pest or Pathogen Spread Prediction System, which they developed to track everything type of pest or disease. Their system combines information on the climatic conditions conducive to the spread of the pest with data on where cases have been recorded, the rate of reproduction of the pest and how it moves through the environment. environment. New data is helping their forecasting system better predict future spread.

To track the spotted lanternfly, the researchers used observations collected by state and federal agriculture and pest experts between 2015 and 2019. They considered rail networks to be a “high-risk” route for the spread of the spotted lanternfly on the west coast, as it is a hitchhiker. pest that can lay its eggs on many different surfaces, including vehicles. People can accidentally move the insect when transporting shipping materials, rock, railroad cars, or even vehicles where the insect has laid its eggs.

“The main reason we included proximity to the rail network in our model is that it is strongly correlated with long-distance dispersal,” Jones said.

In addition to factoring the proximity of a railway track into the insect’s spread, the researchers also speculated that the insect requires the presence of the invasive host tree – the sky tree or Ailanthus altissima – for most of the insect’s reproduction. Researchers said the tree often grows along highways and railroads.

“We assumed that the spotted lanternfly needed a sky tree to complete its life cycle,” Jones said. “The presence of the tree of heaven, as well as railroad networks, seem to be two factors that could favor the spread in California. The temperature there is relatively suitable throughout the state.

Researchers expect the spotted lanternfly to be established in much of the United States by 2037 if all efforts to control it are stopped.

In California, researchers said the insect has a low probability of reaching wine-growing counties by 2027 and a high probability by 2033. They expect it to spread through the wine-growing region of California. 2034.

“When we say there is a ‘high’ probability of reaching these counties, we mean there are several counties that have a probability of over 50%,” Jones said.

They predicted that there would be a high probability of the insect spreading to North Carolina by 2027. The spotted lanternfly has already been identified in Virginia, and forestry experts in North Carolina are following it closely. The researchers said they are working to educate growers here.

“We are currently conducting risk assessments and developing companion maps to educate North Carolina growers and other managers to help them prioritize management strategies,” said the study’s co-author. . Ross MeentemeyerGoodnight Distinguished Professor of Geospatial Analytics at NC State.

The researchers said their findings could help state and federal authorities protect American crops like grapes, an industry valued at about $6.5 billion nationally. Their findings provide a baseline for their management strategies. Additionally, officials can use their computer modeling system to test the results of different management strategies.

“We hope this will help pest managers prepare,” Jones said. “If they can start monitoring early or start treating as soon as the spotted lanternfly arrives, that could slow the spread to other areas. They could also preemptively remove the sky tree around the vineyards.


Note to Editors: Summary follows.

“The spotted lanternfly is expected to become established in California by 2033 without controlled management

Authors: Chris Jones, Megan M. Skrip, Benjamin J. Seliger, Shannon Jones, Tewodros Wakie, Yu Takeuchi, Vaclav Petras, Anna Petrasova and Ross K. Meentemeyer.

Posted online in Communications Biology June 8, 2022.

DO I: 10.1038/s42003-022-03447-0

Summary: Dynamic models in both space and time are needed to predict where and when non-native pests and pathogens are likely to spread, in order to provide advance information to natural resource managers. The potential range in the United States of the invasive spotted lantern (SLF, Lycorma delicatula) has been modeled, but until now it was unclear when it might reach the West Coast’s multi-billion dollar fruit industry. We used process-based modeling to predict the spread of SLF assuming that no treatments to control populations occur. We found that SLF has a low probability of first reaching California wine counties by 2027 and a high probability by 2033. Our study demonstrates the importance of spatiotemporal modeling in predicting the spread invasive species to serve as an early warning. for growers and other decision makers to prepare for imminent risks of SLF invasion. It also provides a benchmark for comparing future control options.