Celebrating Cottonwoods
by lead teacher naturalist, Susan Snyder
Ah, the sights and sounds of spring at Ogden Nature Center. Birds warbling in the trees. Chorus Frogs peeping from the ponds. Visitors sneezing as floofy cotton drifts down from the cottonwood trees.
The Nature Center has two types of cottonwood trees: Fremont, and Black Cottonwood. Both species are typically seen growing along rivers, streams, and other riparian areas in the West. They are the first trees to sprout after a flood, because they seek water and thrive in wet environments – even if surrounded by a dry one.
But let’s get back to sneezing. It’s not the fluff – really! The fluff that emerges in late spring and early summer is the seed from female cottonwood trees. Cottonwoods are dioecious – which means some trees are male and some are female. Male trees produce and spread pollen. Female trees produce and spread seeds. The cottonwood fluff acts like a tiny parachute that can be carried up to five miles. But the fluff has no pollen or properties to cause sneezes. Pollen, not seeds, cause sneezing, and cottonwoods release pollen weeks ahead of the fluff – around early April.
Experts say the reason people sneeze when the cottonwood fluff flies is because other high allergen producers are pollinating at that time – mostly grasses. But we don’t see that pollen. We see the cottonwood fluff, and so it takes the blame.
Cottonwoods are a highly useful tree for insects, animals, and people. For example, honey bees collect the sticky resin from the Black Cottonwood buds, and take it to their hives, where it acts as a sealant and antimicrobial agent that prevents bacterial and fungal growth.
Indigenous people have used the resin to waterproof baskets and infused it into oil to make a salve to soothe muscle and joint aches.
Like willow trees, cottonwoods contain salicin – the analgesic chemical from which early aspirin was made. So it helps reduce fevers and inflammation. Cottonwood trees often are the only trees growing for miles on the open prairies and Great Plains, providing shade and landmarks for early travelers across North America.
You can even eat cottonwoods! The sap is said to be sweet enough to drink, and can be boiled to a syrup akin to that of maple trees. The inner bark and buds also are edible, by some accounts. And if you ever find yourself in need of something to help spark an evening campfire in summer, a wad of the fallen cotton makes a great accelerent.
So when early summer rolls around, feel free to frolic in all of that cotton! It’s just happy little trees spreading their seeds.
