If you can find the Cariboo Mountains on a map of British Columbia ... you can probably spot the answer to our Geo Quiz.

It's the city of Williams Lake.

It's a cool 62°F there today....just a hint of the much chillier temperatures soon-to-come in western Canada. This year locals are actually hoping for a frigid winter. That's because a deep freeze is what's needed to kill off a tiny predator that's been eating away at their trees. The World's Andrea Crossan has more.

From the air, the forest surrounding Williams Lake in central British Columbia looks like a patchwork quilt of red and green. The green trees are a mix of fir and spruce. The red trees are lodge pole pine. Almost half the landscape is dotted with the rust colored trees. All of them dead.

On the ground, things look even worse. Take a walk through the forest here and it's hard to find a healthy pine. Most of the trees have already been killed or are currently under attack by a bug that's the size of a grain of rice.

Kerri Howse is the Stewardship Forester in this area. Howse carves a small patch of bark off a young lodge pole pine tree. She spots the tell-tale entrance hole of a mountain pine beetle.

Mountain Pine Beetle

Howse: Hah, OK so there's an adult pine beetle. It's the tunnel where the female goes up and she lays her eggs on the side of what they call the main gallery and then the larvae actually eat their way from the main gallery outwards.

It only takes a few dozen of these tiny black beetles to kill a pine tree. They burrow into the tree's bark to lay their eggs. The larvae hatch and feed on the tree. Mountain pine beetles are indigeneous to Canada and parts of the U.S. There have been infestations in the past. But nothing like this.

Howse: They're all getting very desperate because their running out of adult trees to attack so their attacking smaller trees, like ten years ago this tree would never have been attacked.

In the last years mountain pine beetles have eaten their way through over 35,000 square miles of British Columbia's forests. That's an area the size of Massachusetts, Vermont, and New Hampshire combined. And experts believe the infestation is likely to spread as temperature conditions for the beetle get warmer.

Carroll: Things have been improving quite dramatically in the last 30 or 40 years for the mountain pine beetle in western North America

Dr Allan Carroll, is a research scientist with the Canadian Forest Service. He says that the current beetle infestation is not linked to a change in the beetle's food source - it's the change in the climate. The beetle can't survive extreme cold weather where temperatures stay between -22° and -40° F for several days. But global warming has meant that winters here no longer get cold enough to kill off the bugs.

Carroll: Areas that the mountain pine beetle previously couldn't occupy are now available to it, their now suitable for it and it can actually establish there and persist where previously it couldn't simply because winters were either too cold or the summers were too cool. And so we've had a rapid expansion of the available habitat and at the same time the beetle has moved very quickly to occupy it .

But experts are drawing on a new weapon in the battle against the mountain pine beetle: pheromones. They are using the beetles own pheromones to both attract and repel beetles from the pines. Some pheromone packets tell the beetles that the tree is already fully infested, much like posting a no-vacancy sign. Other packets emit a pheromone that attract a beetle to an individual pine. That causes the bug to fly into a trap hanging on the tree.

Kerri Howse says that the traps are used around sawmills to keep the beetles from flying back into the woods.

Howse: What it does is it draws the beetles to this trap and they fly into the tunnel when they are attracted to the lure and they fall into the cup and then they can't get out again, so they put these all around the mill yards to try and capture beetles so they don't fly out into the forest.

Mountain pine beetles are expected to wipe out 80 per cent of British Columbia's pine forest in the next 5 years. Now the race is to stop the beetle's eastward expansion.

Research scientist Allan Carroll explains why what's happening in this part of Canada could become a major problem stretching from the west coast of North America all the way to the eastern seaboard as temperatures increase.

Carroll: The Boreal forest has a species of pine in it that we know to be susceptible to mountain pine beetle and further to that some of the climate change scenarios that the climatologists have developed we predict that within the next ten or twenty years the Boreal forest will become a suitable place for the mountain pine beetle which would then allow the beetle to expand there and continue moving eastward, conceivably as far as the east coast, down the road.

Here in Williams Lake, a cold winter could help to slow this current infestation. But the beetles aren't likely to be causing more damage here in years to come. There just aren't enough pine trees left for them to eat.

For the World, I'm Andrea Crossan, Williams Lake, Canada.