Does warm weather in February mean an early pollen & allergy season? What to know.

We’ve had a warm week — and month, really — as high temperatures in the Triangle on Thursday set all-time records for the month of February.

With all of this unseasonably warm weather, you may have started to notice symptoms of the dreaded seasonal allergies, from itchy eyes and noses to sniffling and sneezing.

Your symptoms aren’t deceiving you. With the recent warm-up in temperatures — happening about two to three weeks earlier this year, compared to normal — pollen season is setting in early, Kelly Oten, an assistant professor and forest health specialist at N.C. State University told The News & Observer.

What’s behind the early start to pollen season? Will the season last longer this year?

We talked with Oten to get answers to those questions and more.

Here’s what to know.

Where does pollen come from?

First, it might be helpful to understand where pollen comes from, and how it even gets into the air.

“Pollen is part of a tree’s reproductive system,” Oten said. “It contains the male DNA and it needs to find a way to get to the female receptors which are within flowers.”

The pollen that affects our seasonal allergies generally comes from wind-pollinated trees, Oten said. Those are trees that — like the name suggests — become pollinated by pollen that moves through the air, instead of being pollinated by insects, such as bees, or other animals, such as birds and bats.

“Plants that are pollinated by insects don’t produce as much pollen because pollination is more intentional and direct, so they don’t need to produce or emit a lot of pollen,” Oten said. “But some trees are pollinated by wind, so they produce massive amounts of pollen that go airborne. It’s the massive amounts of pollen produced by wind-pollinated trees that makes everyone mad every allergy season.”

In North Carolina, “we have a decent amount of wind-pollinated trees,” including oak and pine trees, Oten said.

Ragweed and some flowers with “high pollen loads” can also contribute to seasonal allergies, Oten said.

What type of pollen causes allergies?

While the yellow pollen we tend to see covering our cars or water surfaces each spring is a good indicator that pollen is in the air, that kind of pollen — which, in North Carolina, often comes from our many pine trees — is generally too large to get into our lungs or affect our allergies, The News & Observer previously reported.

“When people are experiencing allergies, it is usually because of the smaller pollen in the air,” Oten said.

“Smaller-sized pollen can penetrate lungs deeper and cause allergies to be worse. Right now, we have cedar pollen and elm pollen already being spread, both of which are smaller size pollen compared with pine, for example.”

What’s making pollen season start earlier this year?

Warmer temperatures arriving earlier in the year are contributing to an earlier start to pollen season this year.

That’s a trend that’s becoming more common, as the climate continues to warm, Oten said.

Will pollen season last longer, be worse this year?

Along with earlier starts to pollen season, climate change and warming is also changing the length and intensity of climate season.

“Several papers have shown not only are we getting earlier pollen seasons, but they’re longer pollen seasons,” Oten said. “And on top of that, they’re more intense, since we’re seeing more pollen produced.”

Oten cited a study published last year, which predicted that some trees will produce up to 250% more pollen in the future. The study predicted that, in the next 60 to 80 years, pollen season could start up to 40 days earlier and last about 19 days longer, Oten said, with total pollen emissions increasing between 16 to 40%.

SImilarly, 2021 study in the Proceedings of the National Academy of Sciences found that trees produced 21% more pollen in 2018 than they did in 1990.

“You hear anecdotally that allergy season is getting worse,” Oten said. “It is.”

When is pollen season the worst in NC?

The N&O previously reported that the highest pollen counts in the Triangle — specifically in downtown Raleigh — have been recorded between the last week of March and the second week of April, according to counts from the state Department of Environmental Quality (DEQ).

Pollen counts can also vary by the time of day, with counts being higher from about 5 to 10 a.m., then declining throughout the day, The N&O reported in 2021.

You can track Raleigh pollen counts from DEQ at twitter.com/NCpollen, where counts are reported each day they’re collected.

Reporter Adam Wagner contributed to this story.

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