France, Aug. 30 -- Wildfires that ripped through Europe this summer, forcing thousands to flee and leaving vast areas of forest in ashes, were the worst the continent has seen in decades. Scientists say climate extremes are driving the destruction. Yet forests have an incredible capacity to recover - sometimes naturally, and sometimes with human help.

In recent years, forest fires have destroyed millions of hectares of vegetation in North America, southern Europe, Australia, and especially in Africa.

Once the flames die down, forests can regenerate naturally or with intervention. Depending on the trees and the location, recovery can take anywhere from three to 60 years.

Forests can recover if the right conditions are in place - whether...