The late spring dispersal of cottonwood seeds happened throughout last week–and into this one. I couldn’t find any ready information about variance in seed volume by year, but the amount of seeds in the air seemed greater this year.
A low-hanging catkin in a nearby park with closeups of seeds, mid-release:
Seedpiles could be found everywhere, piling up so high and thick they were like snow on the grass
In less cultivated environments, the eastern cottonwood (Populus deltoides) is more of a niche species, occurring near rivers and water sources, where the seeds need constant moisture to germinate and grow. These seeds are notably short-lived (the US Department of Agriculture’s Woody Seed Manual reports they stop being viable in as little as two weeks). Unlike some seeds, which can remain dormant for a long time until conditions improve, the cottonwood appears to be a prolific producer of low-odds seeds that travel far. Most will waft off course and die off right away, but the hope is that a few float far enough to hit the right habitat–and take off.
The city of Chicago probably likes to plant them in cultivation because they are fast growers (some sources say one of the fastest, 6 or more feet a year), reaching a mature height in 10-15 years.
Because of a few favorable qualities, this tree with a picky survival strategy gets to live everywhere in the city.
plants spring event