Look at the twig on the end of the branch. The leaf buds, what will be leaves, are yet encased in two small pointed scales, long, thin, dark-red like witches' fingernails. Clusters of catkins appear before the leaves. The male and female catkins form on separate twigs. The flexible, dangling male catkin has flowers and bracts.
Bracts are woody parts, resembling scales, under flowers similar to the scales of a pine cone.
Flowers without petals. These miniscule structures produce the vast clouds of pollen, released at the slightest touch or breath of air, found on your hands, on your clothes, beneath your feet. The female catkin resembles a small pine cone and remains on the tree after the seeds fall out.