Got caterpillars? Try salt and Vaseline, says Manitoba gardener

In what's beendeemed the "year of the caterpillar," a Manitoba gardener says she's found a cheap trick for stopping at least some of the insects from munching on her trees salt and Vaseline.

Eleanor Beever experimented with the mixture a paste that's half salt and half petroleumjelly by applying it in a ring around the trunks of her favourite trees nearly two weeks ago.

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So far, she said it has stopped the creepy crawlies dead in their tracks.

"They'll get to the perimeter of it and then they'll rear their heads in the air and wiggle, and then they'll make a U-turn," said Beever, who owns a greenhouse in Rivers, Man.

Beever suggests removing the Vaseline with soap and water after the worst of the caterpillar season is over.

Ken Nawolsky, the City of Winnipeg's superintendent of insect control, said the idea could work.

"I don't know about salt but Vaseline definitely is enough of a sticky substance that it would prevent [caterpillars] from going up," Nawolsky said.

While banding is not effective against elm spanworms or tent-forest caterpillars, it can work for cankerworms.

A petroleum jelly band also won't get rid of insects already on the trees, Nawolsky said, but it may discourage all three speciesfrom climbing up atree.

"That would definitely be a deterrent from them crawling up the bark of the tree."

This spring has been an usual one for tree-eating insects because there are three species attacking foliage at the same time.

"Typically, you only see one or two species at a time but this year we have the forest-tent caterpillars, the elm spanwormand the cankerworms," said Nawolsky.

Forest-tent caterpillars are largely done their life cycle for this year but spanworms and cankerworms are still feasting on Winnipeg trees.

Nawolsky said they are particularly bad along neighbourhoods that border the Assiniboine River, especially in West Broadway.

"They always seem to concentrate around that area and we're not sure why," he said.

The city is spraying a biological insecticide this week, whichinfects worms with a bacteria that proves fatalaftertwo or three days.

"We should be making some progress if the weather cooperates in the next few days,"Nawolsky said.

The good news is that despite the fact the insects can leave trees almost entirely bare, they don't actually cause stress to a tree in the long run.

Nawolsky said once they'regone, leaves will regeneratein about three weeks.

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