Catkin-bearing plants include many trees or shrubs such as birch, willow, hickory, sweet chestnut, and sweetfern (Comptonia). In many of these plants, only the male flowers form catkins, and the female flowers are single (hazel, oak), a cone (alder), or other types (mulberry).

What tree has red catkins in spring?

While most other alder trees produce yellow catkins, this tree has reddish-purple catkins that appear each spring.

What tree has pink catkins?

Again, hazel catkins hold the male flowers. Much smaller, but even more fascinating are the female flowers of common hazel. They put forth small but brightly pink structures that give the impression of some kind of alien tentacles.