Desert broom nothing to sneeze at

Ah, but for all its fluttering flowers and cottony seed clumps, the broom might be getting a bum rap as an allergen at this time of year.

"We're seeing lots of desert broom flowers and strands blowing all over right now, but they're not necessarily causing allergic reactions," said Mark Sneller, an allergen expert who operates Aero-Allergen Research in Tucson.

The reason has to do with the season.

"With desert broom, you have the pollen produced in vast quantities in October," Sneller said. "In October and into November, people have significant allergic reactions to desert broom."

But this month, in a season when the plants are past the pollen stage, "what you're looking at now are the seeds and flowers," Sneller said.

"They produce little strands of cellulose floaters, but those are just to keep the seeds airborne so the seeds can travel and reproduce," he said.

It's not known for sure if the little strands are allergens, Sneller said.

"But they're not inhaled because they are too big, so you might not respond to them as an allergen," he said.

He noted that plants can produce other particles - from stems, leaves and flowers - that are small enough to be breathed in and might cause a reaction in some people long after the pollen season.

If you're experiencing allergy problems now and it's not desert broom, what might it be?

Sneller said he has recently detected "everywhere from half a dozen mold spores per cubic meter of air to 3,000 or 4,000 per cubic meter of air. These can be allergens.

"It might also be pollens of ornamental juniper," he said.

Contact reporter Doug Kreutz at dkreutz@azstarnet.com or at 573-4192.