Identifying common catkins
Hello! This guide is here to help you quickly and easily identify some of our most common trees by their catkins. Simply scroll down and browse the catkins available to see which looks similar to the one you wish to identify, then click the link below each image to visit that tree’s profile page to see its other clues and check its identity. Please note, I have not yet completed all the tree profiles, so only some of them are linked.
All about catkins
Did you know catkins are actually flowers? In fact, catkins are made up of tens or hundreds of little, tiny flowers and their proper name is an inflorescence. Not all trees have catkins, and some, like aspen, have catkins that grow really high up on the tree so you might not realise they even have any. Then, there are trees whose catkins you cannot miss – like hazel. Some are round and fluffy, like willow, while others are long soft and dangly – like birch. Then, immature and mature catkins can look quite different. The young, immature catkins are often short, tough and stubby – in contrast to their soft, fluffy older selves.
As any flowers, there are two types – masculine and feminine. Some trees, such as willow, have their male and female flowers on different trees (these are called dioecious), while others, such as alder, have both genders on the same tree (called monoecious). To reduce cross pollination, the male and female flowers of monoecious trees might mature at different times, or the female flowers will grow nearer the top so they are not pollinated by the pollen clouds of the male flowers below.
The catkins you are most likely to spot on your nature walks, are alder, aspen, birch, hazel, poplar and willow. Oak flowers also grow in a catkin, although they might not look typically catkiny!
At the moment, not all the catkins are shown here. I hope to illustrate and add them soon x