Why are Aspen Leaves Always Trembling Nature Insights

The leaves of the Aspen tree (Populus tremula) have laterally flattened stalks (petioles) that makes them move in the slightest breeze - this video explores the reasons why. Aspen is a native tree to the UK and has the habit of producing underground suckers that make clonal trees cover large areas. The World's oldest living thing is said to be an Aspen clone.