Harmful insects

The Spotted Lanternfly: A Beautiful Invader on Canada’s Doorstep

I’ve almost given up on frost-sensitive containers, such as terracotta ones. Although they’re my favorite style, I can’t bring myself to empty them of their potting soil and put them away for the winter. So I opt for sturdier pots, even if they’re less aesthetically pleasing. A sacrifice in the name of Laidbackness!

I say “almost” abandoned, because I still have a few that I use as focal points by planting flowering annuals to brighten up the terrace in summer. With the first autumn frosts, it’s time for gardeners to protect their pots for the winter. But be careful! By taking them inside, you run the risk of unwittingly protecting an insect on Canada’s list of regulated pests: the spotted lanternfly.

The adult spotted lanternfly. Source: Inspection Canada.

A Beautiful Invader

Beneath its elegant looks and colorful appearance, the spotted fulgore (Lycorma delicatula) is a true camouflage artist and a visual delight… before proving to be an ecological nightmare. Measuring around 25 mm long and 12 mm wide (1 inch x 1/2 inch), this insect doesn’t go unnoticed. Its light-brown or grayish forewings are decorated with speckled patterns. The base of the wings is covered with small black dots, while the top features dark stripes that look almost hand-painted.

The hindwings are bright red with eye-catching black dots. This hint of red is followed by a central white band, while the wingtips are deep black with small white fan-shaped lines. Add to this a yellow abdomen with black stripes, and you’ve got an insect that’s hard to confuse with any other in Canada!

The larvae of the lanternfly are equally distinctive, starting out black and white, then acquiring red as they grow. A beautiful mix of colors, but beware: this is not a garden guest you want to see proliferate!

From Egg to Adult

The spotted lanternfly begins its cycle as a winter-hardy egg, laid by the female as early as September. The eggs, clustered in masses of around 2.5 cm (1 inch), resemble small seeds arranged in tight rows, and are protected by a grayish waxy substance that camouflages them. This coating degrades over time, but their distinctive appearance persists.

Egg mass – October to June.Source: Inspection Canada.

Eggs hatch in spring, generally from April to June, releasing larvae that climb trees to feed on the sap of young leaves and stems. At each stage of development, the larvae, first black and white, then red, alternate between the treetops and the ground, ascending and descending in a cycle that increases as they grow.

Young larvaes. Source: Inspection Canada.

In July, mature larvae transform into recognizable adults, ready to continue their cycle and reproduce, thus completing an annual generation.

Voracious Appetite

The spotted fulgore is a real glutton when it comes to host plants. This little stinging-sucking invader is very fond of “phloem”, a sugary substance essential for plant growth. Its menu is varied, and it attacks both fruit trees and deciduous trees: apple trees, cherry trees, poplars, maples and oaks are all on the menu, as is the Ailanthus altissima – its favorite host. This plant, often referred to as the tree of heaven, is an invasive species in its own right!

The Tree of heaven (Ailanthus altissima) is a host of choice for the spotted lanternfly. Photo: seven75

The problem with the spotted lanterfly is that it doesn’t just nibble a little here and there: it settles in groups and feeds on sap, weakening stems, leaves and petioles. The damage is clearly visible. By sucking this precious sap, it can reduce plants’ capacity for photosynthesis, slowing their growth and, in time, even killing them.

And that’s not all! The adults leave behind sugary secretions, called honeydew, which encourage the formation of molds and fungi. This phenomenon can literally smother plants under a layer of black mold, cutting off their access to light and adding further stress that can lead to their decline.

A Fearsome Stowaway

The spotted lanternfly spreads efficiently and insidiously. This insect moves over short distances by walking, jumping or flying. But the real master stroke is its ability to travel long distances… effortlessly! It simply lets itself be transported by us human beings. Its eggs, laid in small brown clusters on smooth surfaces, can be deposited on cars, garden furniture, firewood, farm equipment and many other objects.

So, without realizing it, when we move these objects, we’re also transporting their eggs from one place to another. In short, a simple move or the transport of equipment from one place to another can transform a localized colony into a widespread invasion!

On Canada’s Doorstep

Originally from East Asia, the spotted lanternfly landed on the American continent in 2014, and was first observed in Pennsylvania. Since then, it has expanded its territory to neighboring states such as New Jersey, Virginia and New York, forming impressive colonies. The American authorities are on the alert, as it represents a direct threat to vineyards, orchards and forests. Several awareness campaigns and control measures are in place to try and limit its movements.

Older larvae – July to September.Source: Inspection Canada.

In Canada, it has not yet established colonies… but it may only be a matter of time! A few eggs have been intercepted on shipments from the United States, but for the moment, it hasn’t conquered our gardens. Sightings of the insect, dead or alive, have been reported in Manitoba, Ontario, Nova Scotia, New Brunswick and Quebec. However, the Canadian Food Inspection Agency (CFIA) is keeping a close eye on any sightings of spotted lanternflies, because if this insect were to become established, it could disrupt some of the country’s important agricultural and natural sectors.

Preventing the Spread

To prevent the spread of spotted lanternfly, it’s essential to adopt a few simple but effective measures. Before moving off, it’s a good idea to carefully inspect your vehicle, trailer or outdoor equipment such as ATVs. Keep an eye on your garden furniture and equipment, as well as your flower boxes. As for firewood, buy locally and leave any unused wood on site to avoid transporting eggs from one region to another.

If egg masses, eggs or larvae are discovered, destruction is the best option. Scrape and soak egg masses in soapy water or rubbing alcohol to prevent them from hatching, and crush larvae or adults as soon as possible. To report sightings, contact the Canadian Food Inspection Agency (CFIA).

In the United States, contact your State Plant Health Director, to report sighting.

By adopting these simple measures, everyone can help protect our environment from the ravages of this beautiful invader.

Mathieu manages the jardinierparesseux.com and laidbackgardener.blog websites. He is also a garden designer for a landscaping company in Montreal, Canada. Although he loves contributing to the blog, he prefers fishing.

4 comments on “The Spotted Lanternfly: A Beautiful Invader on Canada’s Doorstep

  1. heathergrammie

    Oh, no! I’m already battling a fearsome number of Japanese beetles each summer. The idea of another voracious pest hitting my beleaguered garden is worrisome. Thanks for the information. I’ll keep my eyes peeled.

  2. How old is this article?

  3. Christine Lemieux

    Hmmm, I saw one of the adults in my garden 2 years ago. I will report if I see one again.

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