Cottonwood fluff, a common sight during spring in Seattle, is not the primary cause of seasonal allergies, according to experts. While often mistaken for an allergen, the white fluff consists of seeds and can pose other issues, including fire risks and potential problems for home air conditioning units.
Rather than triggering hay fever, the cottonwood fluff consists of seeds that act as a nuisance, collecting on surfaces. Allergy experts identify grass and other tree pollen as the main culprits behind seasonal allergies.
Master Gardener Ciscoe Morris clarified that the fluff is not pollen, despite common belief.
“Half the people I talk to, they’ve got hay fever like mad,” he said. “It’s not the cottonwoods.”
He also noted that while the seeds may enter the mouth or nose, “they’re not going to do anything serious.”
The visual presence of the fluff is notable.
“It’s snowing right now, as you can see,” said Jim Fredricksen, walking his dog in Seattle Wednesday.
“It gets everywhere,” said Margaret Stine in Seattle. “It clings to your shoes.”
Morris also warned of the seeds’ ability to sprout.
“You may have some cottonwoods coming up in your garden, if you’re not watching,” he added.
Cottonwood fluff is flammable, though, posing a fire risk.
Everett Fire officials confirmed that in warm, dry weather, piles of cottonwood seeds can ignite quickly and contribute to the spread of small outdoor fires.
They recommend raking up heavy accumulations, wetting down dry areas, and using caution when using smoking materials, grills, and anything that could create sparks.
The seeds can also affect home HVAC systems by building up inside the systems.
Experts recommend cleaning your unit with a garden hose, not a pressure washer.
The Northwest Allergy Center’s recent allergy count indicated moderate tree pollen, predominantly from cedar and juniper trees, as the primary source of current seasonal allergies.
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