Spotted lanternfly ‘an imminent potential problem’ for Canadian growers

The spotted lanternfly has been designated as a federally regulated invasive species to Canada.

By Tamara Botting

Despite its name, the spotted lanternfly isn’t actually a fly. Moreover, while it may look like a moth, it doesn’t fall into that category, either. In truth, these insects are plant hoppers, more closely related to stink bugs or water bugs.

More important than being aware of the particulars of their moniker, though, is keep an eye out for them, and reporting it if you do spot one, because they are a federally regulated invasive species to Canada.

The good news so far is that “there actually are no established populations yet in Ontario, or anywhere else in the country,” said Emily Posteraro, Program Development Coordinator with the Invasive Species Centre.

However, there have been sightings (which is when someone has reported what they suspect to have been a spotted lanternfly specimen), and interceptions (where a specimen has been confirmed to be a spotted lanternfly).

This record is publicly available on the Canadian Food Inspection Agency (CFIA) website.

So far, there has been no known breeding activity of these bugs in the province, but the sightings and interceptions are concerning.

“We know there’s higher pressure coming from their spread in the United States,” said Posteraro, adding that the spotted lanternfly can be found in 18 different states now, including border states like Michigan and New York.

“With that, it just makes it more likely that they could come up this way,” Posteraro said. “We know that we have both suitable plant hosts and suitable climate for them, so there’s no reason that they wouldn’t be able to survive here as well as they’re doing in parts of the United States, where they’re well established by now.”

The spotted lanternfly is native to China, India and Vietnam. It was first detected in the US just over a decade ago. The species thrives in warm, humid climates.

While the adults and nymphs always die with the frost, the eggs are another matter.

Posteraro noted that Natural Resources Canada is doing research to determine what the hard limit is for the eggs of the spotted lantern fly to survive in the cold; so far, the research has shown that the eggs are still viable after a few days of -25 degrees C (-13 F).

“There definitely is a threshold for how far north they could survive,” Posteraro said. However, “our warming winters obviously don’t help maintain that threshold.”

So, what is the concern with the spotted lanternfly?

Broadly speaking, they are a plant stressor, both through their feeding activity and their excrement.

“More specifically – especially from an agriculture perspective – they do seem to inflict a lot of damage on grape vines in particular,” Posteraro said, which they also have a high preference for – though the spotted lanternfly is documented to feed on over 100 different host plants, including native hardwood trees in Ontario.

Unfortunately, another invasive species – the tree-of-heaven plant – is another viable food source for the spotted lanternfly, and since “it’s all over the place … we know they could be supported by tree-of-heaven” if they were to become established in Ontario.

Posteraro noted that the spotted lanternfly will feed on fruit trees as well, though they don’t seem to inflict as much damage.

“They’ll feed and they’ll move on,” she said. When it comes to grape vines, though, there is a definite threat to the plant’s health, “and then obviously, the grape and wine industry that are dependent on them.”

Even if other types of plants and trees aren’t as susceptible to damage, “It might still pose a problem for the orchard in terms of people visit, they maybe don’t want to see bugs all over it.”

Another possible economic impact from the spotted lanternfly could come if it’s found on nursery stock and certain types of wood products.

Posteraro noted that even if the spotted lanternfly wasn’t doing a lot of damage to the trees or necessarily killing off the nursery plants, “they can’t have (the spotted lanternfly) in their product and then be moving it, because it’s a regulated species at the federal level, so that would impact their operations.”

As far as trying to combat the spread of the spotted lantern fly, the main tool right now are the monitoring protocols, which can be found on the CFIA website, as well as on the Government of Ontario website.

“We say, ‘If you spot it, snap it, catch it, and report it,’” Posteraro said, adding that her organization always reiterates CFIA’s messaging, because they’re the leading federal body that has jurisdiction over the spotted lanternfly.

Snapping a photo of the suspected specimen helps create a record of it, but ideally CFIA wants the actual specimen, because that’s how their labs are able to confirm the species. The specimen doesn’t have to be alive to be tested; Posteraro also noted that there’s no risk to humans of bites or stings from a spotted lanternfly.

Once you’ve preserved the specimen, contact CFIA – either through the website or your local office – for instructions on how to submit it.

Anyone wanting to learn more about the spotted lanternfly can access resources through the Invasive Species Centre, including an online course that is offered free of charge, and that participants can take at their own pace.

As for when the spotted lanternfly might get established in Ontario, it’s a bit uncertain – though it does seem to be a bit more of a question of ‘when’ rather than ‘whether.’

“It could be next year. We were expecting it this year; we were expecting it the year before,” Posteraro said. “It’s an imminent potential problem right now.” 