Old Tjikko

This ancient, 16-foot tall Norway spruce lives in the scrubby Fulufjället Mountains in Sweden. At 9,550 years, Old Tjikko is the oldest single-stemmed clonal tree, and took root not long after the glaciers receded from Scandinavia after the last ice age. To figure out the hardy spruce’s age, scientists carbon-dated its roots. For thousands of years, the forbidding tundra-climate kept Old Tjikko in shrub form. But as weather warmed over the last century, the shrub has grown into a full-fledged tree. The spruce’s discoverer, geologist Leif Kullman, named the tree after his dead dog.