Aspen trees are the mostly widely distributed native tree species in North America, found throughout many northern U.S. states, the entire length of the Rocky Mountains, and a huge swath of Canada. But what comes to mind when people think of aspens? Colorado. That’s because we have more aspen trees in thicker concentrations than anywhere else in the U.S., from 5,000 feet in elevation where desert meets foothills to 12,000 feet above sea level, high in the mountains.

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Aspens also provide the Centennial State’s only real fall colors, turning a brilliant gold in the short period between the end of summer and the first snows of autumn as chlorophyll drains from the leaves. Few scenes in the mountains are as stunning as an aspen forest in fall where white bark and golden leaves are flanked by snow-capped peaks.

So why is the aspen so prevalent in Colorado? According to the U.S. Forest Service, elevation is one answer. With the highest average elevation of the Lower 48, there’s plenty of terrain for the trees to thrive. Another reason, according to the U.S. Forest Service, is the tree’s aggressiveness. After large wildfires – of which Colorado has had many – it is usually the first tree species to colonize a burned area. Aspens are also more resistant to fires than their evergreen neighbors.

Once established, the trees can live 150 years or more, until conifers like lodgepole pine and blue spruce have repopulated the area and grow above the aspens, which rarely rise higher than 50 feet.

Aspen trees also have some unique properties to set them apart from other trees in the West.

The white bark carries out photosynthesis for the tree, which in trees is usually carried out by the leaves, according to the National Wildlife Foundation. That means in winter after the leaves have turned gold and fallen and snow blankets the forest, the tree continues to produce sugar for energy. And that’s good news for the deer and elk and other animals that eat the bark.

Another unique thing about aspen trees is their ability to clone themselves. While the tree does produce seeds, a process known as “cloning” does most of the reproduction (cloning occurs when roots sprout new trees that share an identical genetic makeup). There can be many clones in an aspen grove or the entire grove can be one clone, whose leaves all turn at the same time. In fact, there’s an aspen clone in Utah that covers 100 acres and has been estimated at 40 times the weight of a blue whale, making it the largest living thing on Earth – not to mention the oldest. Its age has been estimated at 80,000 years.

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The average age of a clone is 10,000 years. So next time you’re hiking through an aspen grove that is green in summer or taking in the fall colors from along the road, stop to think of how many times this organism has been through this cloning cycle, and how it will continue long after our own human cycles have ended.