Las Vegas Sun

April 26, 2024

Recent rain something to sneeze at

While wildflowers may be blooming from winter rains, so is everything else in the Las Vegas Valley, say experts who found tree pollen levels three times higher on Monday than they had expected.

Mulberry, pine, ash, cedar and juniper are pumping pollen into the air as temperatures warm up and the valley dries out from the weekend showers, said Brenda Whitfield, a Clark County Air Quality Management monitor.

Late Monday afternoon Whitfield finished counting a sticky pollen catcher from Griffith Elementary School near Alta Drive and Valley View Boulevard.

Whitfield found 6,446 pollen grains in a cube of air 3 feet by 3 feet by 3 feet.

Last Friday from the same monitoring station, she counted 281 grains, which is still considered high for the mulberry trees growing across the valley.

"And it has just started," Whitfield said of this year's pollen season. "I expected only 2,000 grains on Monday. Yes, it's high."

The all-time record for mulberry pollen is 65,000 grains in an air sample taken in 1998.

Pollen counts from different trees and plants tend to start climbing in March, said Monte Symmonds, senior monitoring technician with the county's Department of Air Quality and Environmental Management.

"This year's spring allergy season is starting a little sooner than normal," Symmonds said. "Our pollen readings started rising in mid-January this year, which is about two weeks early."

"We're expecting higher pollen levels this year due to all the rain, but we won't know if it's one of the worst seasons ever for several weeks," Symmonds said.

Pollen from ash and cedar trees is airborne, as is that from mulberry trees, which are expected to be in full bloom by the end of the week.

Mulberry pollen, in particular, can trigger hayfever and asthma. Other symptoms include stuffy noses, runny eyes and coughing. The worst of the mulberry season should be over by the end of March, just as olive trees start to bloom.

Olive trees are another major source of aggravation for allergy sufferers.

Besides mulberry and olive trees, grass, weeds and other types of trees produce plenty of pollen for seasonal allergies usually ending the late in May.

From March through May, county air quality staff double their pollen collection efforts, gathering grains twice a week at 10 monitoring stations throughout the valley.

The samples are then processed in the department's lab at the County Government Center.

Meanwhile, all those pollinating trees are getting plenty of warmth and sunshine to help them grow and reproduce. The National Weather Service forecasts a high Tuesday in the high 70s, said meteorologist Charlie Schlott.

"We could push 80," Schlott said.

Monday's high of 76 degrees was about nine degrees above normal. The record for March 7 was 84 degrees, set in 1972.

The valley recorded 0.17 of an inch of rain Friday and Saturday, bringing this year's total rainfall to 4.69 inches. Normal rainfall for this time of year is 1.42 inches. Normal average rainfall for an entire year is 4.49 inches.

Fortunately, for the next couple days winds will be a light 5 mph to 10 mph, keeping at least some pollen from spreading.

The warmer temperatures, however, will encourage blossoms to burst.

"It will really bring out the pollen," Schlott said.

archive