About This Plant

The bark of Populus trichocarpa, commonly known as black cottonwood or western balsam poplar, is characterised by its smooth texture and light grey to greenish-grey colour when young. As the tree matures, the bark transforms into a distinctive dark grey or brownish-black hue. In older specimens, the bark often becomes deeply furrowed, creating a visually striking and textured pattern. Populus trichocarpa is renowned for its impressive height, making it one of the tallest deciduous trees. On average, these trees can reach heights ranging from 50 to 165 feet (15 to 50 meters). The species tends to thrive in moist environments, and its rapid growth contributes to its stature.

The Story

Leaf

The black cottonwood leaves are generally broad and ovate, with a pointed tip and a rounded or slightly cordate (heart-shaped) base. The leaf margins are finely serrated, giving them a toothed appearance. These deciduous leaves exhibit a vibrant green colour during the growing season, transitioning to shades of yellow in the autumn before they eventually drop. The surface of the leaf is smooth, and the veins are prominently visible, creating a network of fine lines across the blade. Populus trichocarpa leaves are alternate, arranged along the stem in an alternating pattern rather than opposite each other.

Produce

Black cottonwood produces a distinctive type of fruit known as a capsule. The capsules contain numerous small seeds and are arranged in hanging clusters. The capsules are roughly cylindrical in shape and can measure around 1 to 3 centimetres in length. They are green initially and turn brown as they mature. The release of cottony fibres from the capsules when they split open is a notable feature, contributing to the common name “cottonwood.”
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