Eastern Cottonwood (Populus deltoides) Species Profile

The eastern cottonwood (Populus deltoides) is a tree up to 80-100 ft in height and 3 to 4 ft in diameter. Leaves are 3 to 5 inches long and nearly as wide, with toothed edges. Bark on older trunks is deeply furrowed and ash-gray, though smooth and greenish-gray on younger trees. Both the male and the female inflorescence is a catkin which is initially compact, but eventually unfolds to become longer and hang loosely from the branch. Once the flowers wilt, male catkins turn gray and dry up, and female catkins turn green and lengthen as the fruits develop.

(1) Breaking leaf buds: (4) Increasing leaf A leaf bud is considered size: The majority “breaking” once a green of leaves on the Developing bud leaf tip is visible at the plant have not yet end of the bud, but reached their full (2) before the first leaf from size. Do not include the bud has unfolded to new leaves that expose the leaf stalk at continue to emerge the base. Compare the at ends of developing bud above to elongated stems the breaking leaf bud throughout the below with leaf tips growing season visible. (5) Colored leaves: Do not include (3) Leaves: fully dried or One or more dead leaves that unfolded remain on the leaves visible; plant. do not include dried or dead Phenophase not leaves pictured: Falling leaves

Photo credits: (1) Chris Evans, Illinois Wildlife Action Plan, Bugwood.org, (2) Axel Kristinsson, Wikimedia commons, (3) Paul Wray, Iowa State University, Bugwood.org, (4) J.N. Stuart, (5) Ben VanderWeide.

The USA National Phenology Network | National Coordinating Office 1955 East 6th Street, Tucson, AZ 85721 | Phone: 520-622-0363 December 2013 [email protected] | www.usanpn.org/education Eastern Cottonwood (Populus deltoides) Species Profile

(1)

(1) Flowers or flower buds: Open or (2) (2) unopened flowers. Once you see open flowers (below) continue to report flowers or flower buds.

Open flowers: Flowers are open when the reproductive parts (male stamens or female pistils) are visible. Do not include wilted or dried flowers. Note: If catkins are high in tree and hard to see, flowers Female flowers Male flowers (with are open once the initially compact catkin has unfolded (with pistils visible) stamens visible) and is hanging loosely.

(2) Pollen release: (3) Fruits: One or more flowers A tiny capsule that release visible pollen changes from bright grains when gently green to dull green, shaken or blown into greenish-brown, tan your palm or onto a dark or light brown and surface. splits open to expose seeds with white fluff. Do not include empty capsules.

(4) Ripe fruits: (5) Recent fruit or seed When the fruit has drop: Mature fruits turned dull green, or seeds have greenish-brown, tan or dropped or been light brown and has removed from plant split open to expose since last visit. Do not seeds with white fluff. include fruits that Don not include empty have dropped before capsules. ripening.

Photo credits: (1) Bill Cook, Michigan State University, Bugwood.org, (2) Steven J Baskauf, (3) Nadiatalent, (4) Troy Evans, Great Smoky Mountains National Park, Bugwood.org, (5) Dave Powell, USDA Forest Service, Bugwood.org.

The USA National Phenology Network | National Coordinating Office 1955 East 6th Street, Tucson, AZ 85721 | Phone: 520-622-0363 December 2013 [email protected] | www.usanpn.org/education