5 things you may not know about northern Ontario's caterpillar infestation

Northern Ontario is once again crawling with tent caterpillars.

They are munching their way across the region and leaving few leaves on poplar and birch trees, which are their favourites.

While most northerners are annoyed or grossed out by the infestation, Jennifer Babin-Fenske and her kids in Sudbury celebrate the onslaught.

"We go out in the backyard and they pick out their caterpillar and name it and then release it and it's a one month pet and it's wonderful," says the entomologist, who is also coordinator of the City of Greater Sudbury's Earth Care program.

Dan Rowlindson, the Sault Ste. Marie-based forest health coordinator for the Ministry of Natural Resources and Forestry, says the caterpillars will chew up about 1.5 million hectares of forest this spring.

He says the caterpillar outbreaks comes every 10 years and that surge lasts for three to five years.

"You can almost set your watch by an outbreak cycle," says Rowlindson.

He says the caterpillars can cause real problems for the human population of northern Ontario, but says because this is a native species to our area and a natural process, there is no need to try to control them.

"Mother Nature knows what she's doing out there," Rowlindson says.

5 things you might have known about tent caterpillars

1. The tent caterpillars behind the outbreak don't actually make tents

There are two kinds of tent caterpillars found in northern Ontario. The eastern tent caterpillarhas a white stripe, lays its eggs in tents and doesn't go through dramatic population increases. The forest tent caterpillar lays its eggs in small sacks, has white spots and is the critter that comes by the millions every 10 years or so.

2. Sudbury is a hot spot for infestations of caterpillars and other insects

Babin-Fenske says a study in the early 1990sshowed that outbreaks of tent caterpillars and other bugs lasts longer in Sudbury than other parts of Ontario, likely due to the historically tough growing conditions caused by decades of mining pollution.

3. It looks bad, but the bare forests are actually good for the environment

Rowlindson says the stripping of foliage by tent caterpillars is part of nature's regular cycle. The thinning out of the forest canopyallows light to reach smaller plants, the caterpillars themselves are a good food source for birds and other animals and when they die (and defecate) they fertilize the forest floor.

4. The worms go marching

Tent caterpillars are also known as army worms, because they will actually march in large groups and once they've defoliated an area, they will move to another part of the forest. This sometimes leads to northern Ontario roads being closed.

5. The caterpillar invasion is not a new thing

While we might think of insect invasions as a new thing that comes with the global village, tent caterpillars are native to Ontario and have been breaking out every 10 years for centuries. A search of Sudbury newspaper archives, shows a story back in June 1936 about how trainswere delayed by slippery rails and one from 1988 about how masses of caterpillars were shorting out hydro lines in the Sudbury area.