CINCINNATI -- Maybe you can't see it, but you sure can feel it: Pollen is in the air. Mold, too.
The Southwest Ohio Air Quality Agency knows how much is there because of a spinning device on its roof. That device is a Rotorod sampler, and it collects pollen and mold from the air. One side of an inch-long rod is lightly greased to make it sticky, and the device spins for one minute every 10 minutes.
Put under a microscope, the rods reveal "dots" of allergens. On a day last week, the samples showed elm, juniper and cedar trees were already pollinating.
The air quality agency collects samples twice a day, February from November.
"Pollen release and mold reproduction is fairly dependent on the weather, so it only happens when it's warm," said Christopher Harrison, quality assurance and monitoring coordinator. "During the winter months -- December, January -- it's too cold for anything to reproducing, so we wouldn't have much of a count if we did start counting that part of the season."
For pollen counts:
any measurement of between 0 to 20 is low;
21 to 100 is moderate;
101 to 1,000 is high; and
anything over 1,000 is very high.
"That's at the peak of maybe a tree release or ragweed season," Harrison said.
The air has more mold than pollen -- "there are a lot more places for mold to take hold and reproduce," Harrison said. For mold measurements:
anything below 500 is considered low;
501 to 1,500 is moderate;
1,501 to 5,000 is high; and
anything over 5,000 is very high.
Most pollen comes from trees between February and May. Grasses come out in the middle of the season, and then in late summer -- during those hot, dry months -- Harrison sees an uptick and ragweed and weeds in general.
If you wonder what's causing your allergies to flare up, the agency has daily updates on its website and hotline.
But know this: Harrison said you're likely reacting to what was in the air the day before, because most people's bodies take about 24 hours to react to an allergen.