A look at pollen trends in central NC - Sichuan Dream Catcher Inc.

by: Rachel Duensing

Posted: Jun 5, 2023 / 05:32 PM EDT

Updated: Jun 5, 2023 / 06:24 PM EDT

RALEIGH, N.C. (WNCN) — We all know pollen season is basically our way of life here in North Carolina, but you might be noticing you’ve seen less of that pollen on your cars lately.

That's because it seems like some of our pollen levels are finally starting to go down.

The North Carolina Division of Air Quality measures pollen levels multiple times a week starting in February through November.

According to their data, weed pollen has remained fairly low so far this year, with the exception of a high spike in May. While weed pollen can cause issues in the summer, some allergists we’ve talked to said it tends to be higher and more impactful to our allergies in the fall.

Grass has been a little more variable, ranging from moderate to low in February and March, then jumping up to high in April. Over the past month, measured levels of grass pollen have dropped into the moderate and low range.

In terms of what has produced the highest amounts of pollen so far this year: trees.

From February through early May tree pollen has generally been high or very high. It's only been within the last few weeks that we’ve seen a consistent drop through medium and into the low category.

CBS 17 asked the North Carolina Division of Air Quality how the pollen collection works, and how the public should use these data, and here is their response:

"Pollen samples are collected seasonally (~February – ~October) over a 24-hour period starting and ending around 9 a.m. local time Monday-Friday. A collection rod is rotated in a circular motion at very high speeds (~3600 rpms), trapping pollen grains onto its surface. At the end of the 24-hour sampling period, the collection rod is returned to the laboratory for microscopic analysis. Just prior to analysis, the collection rod is stained with a reagent that reacts with the pollen grain. After a 30- to 60-minute waiting period the pollen grains appear vibrant pink to red when looking through the microscope. We’re able to see surface features of the pollen grains under the microscope, which allows the pollen to be properly identified and counted."

The Division of Air Quality's reports are intended to provide the public with general information on which pollen type is predominant (grass, tree or weed) and the severity of the pollen type (low, medium, high, very high, etc.)

Some pollen types are more severe than other pollen types which may have more or less impact on allergy sufferers than other types of pollen. For example, 60 grass pollen grains may be "high" severity whereas 60 tree pollen grains may be "low" severity and 60 weed pollen grains may be "medium" severity.

During the spring season, tree pollens tend to be highest while the other pollens tend to be low. As summer starts, we’ll see tree pollen decrease while grass and weed pollen increase. That trend will generally continue until the pollen season ends in October/November. We’re heading into grass and weed pollen season for remainder of the 2023 pollen season.

The main reason pollen levels drop this time of year is because we’re coming to the end of the spring tree pollen season. It's hard to put a date on when this happens but a general observation is that pine trees start to show new pine cone formation.

Pine pollen is mainly responsible for the green/yellow dust that covers all outdoor surfaces in the spring. Also, pollen levels will drop due to cool and rainy weather. We should continue to see less pollen on outdoor surfaces until next spring, when the pine trees pollinate again.

It's important to note that our pollen reports do not reflect the current pollen count, but rather recent observations. For example, today's pollen report covers the sampling period from 9 a.m. Sunday to 9 a.m. Monday. We state this on reports but the date differences between sampling to analysis/reporting can be confusing."

To learn more about North Carolina DAQ's pollen monitoring, click here Pollen Monitoring | NC DEQ