Why more trees - not fewer - could save a city from fire

Ten years ago this month the Horse River Wildfire burned through Fort McMurray and into the Canadian consciousness. We hear why experts say it’s the fire that taught us nowhere is safe, even busy urban centres. And, from the best of What On Earth: The Yukon government is betting on a first-in-Canada solution to help protect Whitehorse from wildfire: a permanent fuel break made of trees. But, the process takes a lot of work, starting with harvesting tiny seeds.