CLOVERDALE – The Canadian Food Inspection Agency (CFIA) found a foreign pest that "poses a threat to B.C.’s ecology and economy" in the Cloverdale area of Surrey.
The province considers the European gypsy moth, also known as Lymantria dispar, to be a "threat to B.C.’s ecology and economy."
The Ministry of Forests, Lands and Natural Resource Operations is partnering with the CFIA to eradicate the pest before it becomes established in the city.
The insect attacks both natural forests and urban trees, and in 1999 resulted in the U.S. threatening to refuse shipments of trees and plants from B.C.’s nurseries without additional inspection certificates.
The ministry says the presence of the moths "poses a quarantine threat and potential trade restrictions for products like Christmas trees, logs with bark, nursery plants, and challenges for transportation (trucks may need agricultural inspections)."
The moths were found in Surrey in 2013 through the CFIA’s program, which places pheromone traps in populated areas of the province on a one-mile grid pattern.
That summer, three traps in the Cloverdale area were found to be holding one moth.
This past summer, hundreds of traps were placed from Sullivan Station to the Cloverdale Fairgrounds, and from south Fleetwood to the agricultural lowlands.
A total of 197 male moths were caught.
Following that, ground searches found the moth’s egg masses, each of which can contain hundreds of eggs. Most of the masses were found on street trees growing on the boulevards and medians of 64 Avenue, between 168 and 176 streets.
Tim Ebata, a forest health officer with the MFLNRO, said the size of the moth’s population found in Surrey is "unusually high."
"We’ve been knowing that there was something brewing in that area because we’ve had singlemoth catches over several years but never had enough information to pinpoint where the epicentre was," he said.
Ebata said the moth feeds on more than 300 different shrub and tree species, many which are highly valuable fruit and ornamental trees. He added that the gypsy moths could severely impact the Garry oak ecosystem and other vegetation systems throughout southern Vancouver Island, the Gulf Islands, Sunshine Coast, Lower Mainland and B.C.’s southern interior valleys.
He noted the moths being located in Surrey is particularly concerning because it’s close to many major trade routes.
Western North America is considered gypsy moth free, Ebata explained, which is why the province is aggressive in eradicating any that are found.
"Our U.S. partners will be very interested in seeing how we perform in dealing with this," he added.
Previous provincial cases have been dealt with by trapping, followed by spraying with the pesticide Bt K, which is exempt from the city’s pesticide bylaws.
A City of Surrey memo says the current eradication plan for Surrey "calls for more extensive ground searching in the winter when the leaves are off the trees, to detect and eradicate egg masses, followed by aerial spraying of approximately 12,000 acres in the spring of 2015."
Ebata says the ministry will be publicly announcing its plans at a later time, possibly when they are set to appear before Surrey council next month.
Owen Croy, Surrey’s manager of parks, is confident the ministry and the CFIA will eradicate the invasive species and said the city is on board to help however it can.
He didn’t recall the moth being reported in the city previously, and confirmed it’s the first time in at least two decades.
The pest is often introduced when people move from infested areas around the country or in the U.S., he said.
"Almost always it’s people moving into an area, because it’s the egg masses that get transported – it’s rarely larvae or the moth," he explained. "Egg masses can be laid on things like a tent trailer… if someone is camping in a wooded area where the gypsy moth is present, they may not even know about it… That following spring in April, when temperatures because suitably warm, eggs would begin to hatch."
Croy said staff have received training on how to identify the egg masses, and the city is co-operating with federal and provincial officials in quarantining pruned materials.
As well as anticipated effects on the province’s ecology and economy, an established infestation of the moth could have impacts on residents, as the defoliation would kill many trees, leading to a need for increased pesticide use. The fine hairs shed by the caterpillars also cause dermatitis in many people.
This species of moth was first introduced from Europe into Massachusetts in the U.S. in 1869 in an attempt to breed it with silk worms. The moths escaped, and by 1889 had become a significant pest in the area, reportedly completely stripping trees of leaves, caterpillars covering houses and sidewalks, and larvae and their feces raining down upon passersby.
By 1912, the moth had entered Canada, and was first discovered in B.C. in 1978.
For more information on the province’s eradication program visit For.gov.bc.ca/hfp/gypsymoth/.