What is Blooming in Phoenix?

If you have been sneezing and your eyes and nose stinging and watering you might be asking: “My allergies are driving me crazy, what in the world is blooming this time of year?”

And like many, to find out you might google it, put in your zip code and come up with something like this from Pollen.com.

 

Seems pretty clear. Your sneezing and drippy nose is being caused by all the pollinating Ragweed, Chenopods (whatever they are), and Sagebrush in your neighborhood.

Perhaps not.

Notice in the map above that Arizona, Southern California, Utah, and Nevada all have the same pollen forecast.  All those regions are pretty much the same aren’t they?  Just like all of Arizona is the same, right?

Perhaps not.

Anyone who has taken a road trip from Phoenix to Prescott, Payson, or Flagstaff in August can tell you that the scenery, not to mention the temperature, changes dramatically as you drive north.  Gliding along on the 1-17, your car is like a time machine driving into the future. You leave the pizza oven called Phoenix with it’s scorched earth landscape and toxic ozone haze, and in two hours you’ve travelled from summer to blissful fall.  The leaves are changing, the air is clear, cool and crisp, (sweater weather) and wild grass on the hill side is swaying in the breeze (along with the ragweed, BTW ).

If you were to continue driving north, past Flagstaff, you would enter yet another ecosystem, the high desert, home to many plants not found in the low desert of South and Central Arizona or around the San Francisco Peaks.  Sagebrush for example is a huge allergy problem in the high desert surrounding Winslow and Page but has minimal presence in Phoenix. (Texas Sage, a common ornamental landscape bush, is not a member of the Sagebrush family.)

Because of the differences in elevation and temperature, the unique ecosystems of Arizona have different pollinating schedules.  Ragweed and Sagebrush may be wreaking havoc in Winslow at the same time that the poor ragweed around Phoenix is just trying to keep from drying up and blowing away.  So a pollen report showing that Ragweed and Sagebrush is high in Arizona is technically accurate but misses the mark for those living in Phoenix.

Some pollen reports seem to group all of the Southwest into the same region.  A report from a pollen counting station located in San Diego will give results that will look very strange if you happen to live in Ahwatukee, even though they are both part of the “Southwest”.

To my knowledge, the location of the pollen counting stations for Pollen.com and the weather sites are not listed on their websites.    One of the best sources for pollen levels is the American Academy of Allergy and Immunology.  AAAAI has a rigorous certification process to insure that sights are providing good information. But there is a problem for the Phoenix area.  Below is a map showing the location of certified pollen counting stations in the west.  Notice something missing?

Getting back to the question: “What is blooming in Phoenix”.   This time of year the answer is: “Not much.”

So if pollen counts in Phoenix are low, what is causing all the sneezing, drippy nose, and red, burning, watery eyes in mid August?

For many, this is the problem:

High levels of ground level Ozone, common during the hot summer months in Phoenix,  is a significant cause of respiratory symptoms, particularly for those who have allergies and asthma.

But do not feel left out.  Fall will be coming to the desert soon and along with it the seasonal bloom of grass and weed pollen.  And you won’t need a time machine to find it.

Brian Millhollon, MD