Close-up: Catching the Anti-chemical Bug

If the thought of black widow spiders and deer fly bites has you dreading the onset of bug season, here’s a different perspective: your neighbours may be filling their backyard with preying mantis eggs.

  • Jun. 4, 2011 5:00 a.m.
Sophie Jansen  shows off one of the few remaining preying mantis cocoons still at the Art Knapps store in Kelowna. Anywhere between 40 and 400 of the creatures could come crawling out when they hatch.

Sophie Jansen shows off one of the few remaining preying mantis cocoons still at the Art Knapps store in Kelowna. Anywhere between 40 and 400 of the creatures could come crawling out when they hatch.

If the thought of black widow spiders and deer fly bites has you dreading the onset of bug season, here’s a different perspective: your neighbours may be filling their backyard with preying mantis eggs.

With the wave of interest in urban farming and growing your own food sending suburban families to the nursery in droves, the need for more natural pest control has shopkeepers in Kelowna hopping.

Praying mantis cocoons, bags of ladybugs, Mason bees and creepy crawly nematodes can all be purchased to stave off those “predator bugs” which sever the root systems, munch on the leaves and generally destroy the flowers and produce of local green thumbs.

“They’re a good alternative to chemicals,” said Sophie Jansen, an Art Knapp Plantland and Florist customer service representative whose been on the job for nearly 15 years and holds her pesticide dispensing licence.

Jansen is largely responsible for the live pest control section of the store, which is officially dubbed ‘integrated pest management’ as it offers both insects, natural pesticides like insecticidal soaps, and chemicals—though the City of Kelowna is trying to phase this last option out.

What the store doesn’t sell on the latter front, unfortunately, many customers will opt to simply go south to Penticton to buy as that city has not adopted the same ban on cosmetic pesticides.

Yet every year when Jansen brings out the live bate version of pest control, she notices the insects grow more popular.

“We’ll sell a tremendous amount of ladybugs,” she said. “Everybody loves those.”

The praying mantis cocoons are not quite as popular, and the number of the bugs they produce can sound pretty astounding; between 40 and 400 will hatch within a two-hour time frame from each brown cocoon.

Praying mantises are a long, green, stick-like bug. While there are over 2,000 species around the world, they’re probably best known for one unique quality—the female mantis can, under certain circumstances, decapitate the male after mating. There are pictures of the insects on YouTube so large they can eat mice, Jansen says, though she assures the ones sold at Art Knapp Plantland and Florist are not likely to grow much bigger than a finger and are common in this area.

Ask UBCO professor Robert Lalonde and he’ll tell you introducing the insects sold in local stores is not likely to cause much of a disturbance to the balance of your backyard’s ecosystem.

“Frankly, your backyard has a bigger impact,” he said.

Many of the foreign plant species we routinely plunk in our beds have a far more measurable affect.

The insect is not native to the area, but Lalonde says they can collect them on the UBCO campus they’re now so plentiful. It was introduced in the 1920s in a deliberate attempt to reduce pests in orchards. He’s skeptical on how effective it is, but says purchasing a few won’t hurt anyone else in the area.

The ladybird beetle, or ladybug, offers a lot more pros and cons.

Douglas College instructor and ladybird beetle expert Robert McGregor says the popular red bug with its little black spots is a prime example how introducing an insect can offer a sustainable environmental pest control option or be an environmental disaster, depending on the situation.

Ladybugs are primarily used to control aphid populations, the annoying plant lice, as the British say, which suck sap from healthy plants.

When McGregor began studying the ladybird beetle in the 1980s there were all kinds of native species in the Lower Mainland where he was working.

A few decades later, though, he says he rarely sees a native ladybird. The populations having been overwhelmed by ones like the Multi-coloured Asian Ladybird Beetle, the closest introduction of which was done in King Country, Washington in 1991.

Ladybird beetles have been introduced into areas to huge success. In fact, one such instance really inspired the years of insect release programs governments now use.

In the late 1800s and early 1900s, a pest called cottony cushion scale threatened California’s orange groves, a huge revenue stream for the state, McGregor said.

While the American ladybirds didn’t seem to notice the cottony cushion scale, an Australian beetle,  the Rodolia cardinalis found it so tasty it eliminated the pest in a single year saving the industry.

The Asian Ladybird Beetle offers the cautionary flip-side to such tales.

While it chews through aphids at an unprecedented rate, it also chews through native ladybird beetle larva and has become a nuisance pest in American homes and a real problem for some farmers.

“If you’ve ever picked up a ladybug you might know they have this sort of sticky, yellow substance which can be quite smelly,” McGregor explained.

The yellow liquid is a defensive compound comprised of the sap which has been known to destroy wine grapes; a phenomenon known as ladybug taint.

The more common problem occurs each fall in areas where ladybugs have been introduced as homeowners find hundreds trying to overwinter in their garages and attics, leaving a sticky, smelly mess.

The ladybird beetles for sale at Art Knapp don’t fall into this category.

These beetles, Jansen says, are native to the area and are harvested on Vancouver Island.

While there is little by way of regulation on the industry at this point, import and export rules on companies do ensure there’s oversight on imported insects.

And as those customers travelling to Penticton do point out, the average consumer can be pretty finicky when it comes to using more sustainable methods.

Right now the experts are somewhat divided on whether a registry of some sort might be a good idea, McGregor said.

Anything that drives up price could see insects deemed a little too pesky to bother with in the eyes of the fickle consumer.

For now, he says, it might just be worth letting this unnatural natural intervention continue attracting new customers.

jsmith@kelownacapnews.com

 

 

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