Ernie Janes / Black poplar (Populus nigra) leaf skeleton macro closeup

Pascal Tordeux / Line of Black poplar trees (Populus nigra) at sunset, Surfontaine, Picardy, France.

Jean E. Roche / Bark of an old Black poplar (Populus nigra) Oppedette Canyon, Provence, France, April 2016.

Alex Hyde / Hybrid Black poplar (Populus x canadensis) leaf detail showing venation. Cambridgeshire, UK. September.

Alex Hyde / Hybrid Black poplar (Populus x canadensis) leaf detail showing venation. Cambridgeshire, UK. September.

Floris van Breugel / Frosted Black Cottonwood Trees (Populus trichocarpa), Eastern Washington, USA. January 2014.

Kirkendall-Spring / Black and white photograph of snowy winter landscape with Aspen (Populus) trees in Ashely National Forest, Utah, USA.

Donald M. Jones / Black Bear (Ursus americanus) cub in Aspen (Populus sp) tree, Canada

Yva Momatiuk & John Eastcott / Black Spruce (Picea mariana) at their northern most range in tundra in fall colors, mountain stream rushing down among boulders, and high rocky peaks in first snow, Brooks Range, arctic Alaska

Philippe Clement / Balsam poplar / Black cottonwood trees {Populus balsamifera} in autumn colours, Denali NP, Alaska, USA

Kirkendall-Spring / Black cottonwood (Populus trichocarpa) trees, Sun Lakes State Park, Grant County, Washington, USA. May.

Andres M. Dominguez / Catkins on Cottonwood (Populus nigra) tree, Grazalema, Southern Spain. March.