These dangling fingers decorating the bare branches of gray birch trees hold a secret. Four Winds Naturalist-Educator Chris Runcie has shared their magic with the students at Robinson Elementary School. She says to roll some in your hands and see what happens. Give it a try!
An explosion of seeds! These are the mature female catkins – clusters of flowers that have gone to seed – of gray birch trees. Each catkin is packed with seeds (referred to as winged nutlets) tucked together with bracts (three-lobed modified leaves). Can you pick out the flying bird-like bracts and the smaller butterfly-like seeds in the photo?
Birch seeds are moved by wind and can scoot across smooth snow to disperse, traveling over 250 feet from a parent tree if the conditions are right. Try releasing the seeds to the wind yourself and see how far you can make them travel!
Challenge: Different birches have differently shaped seeds and bracts. Can you pick out the larger yellow birch bracts and seeds from the smaller gray birch bracts and seeds in the photo below?
The yellow birch seed is outlined in a purple square and the bract is outlined with a purple circle.
We have noticed them all winter under our birch trees as well as watched the finches hang off the branches to eat them. Thank you for the great information, Chris. Once again I’ve learned something new from you.