Seasonal Tree, Weed and Grass Pollen Patterns in the Las Vegas Valley
Sunday, March 6, 2016
South Exhibit Hall H (Convention Center)
Hongbin Jin, MPH, BSN, RN, Tanviben Patel, BS, MPH, Mark Buttner, Ph.D., Dennis Bazylinski, Ph.D., Joram S. Seggev, MD FAAAAI

In Las Vegas, the local pollen pattern is unique because of a distinctive subtropical, hot desert climate. A detailed seasonal pollen calendar is required for local allergy sufferers and tourists. The goal of this study was to portray the current pollen patterns in the Las Vegas Valley.


Air samples were collected using a Burkard spore trap from August 1, 2014 to July 31, 2015 at the University of Nevada, Las Vegas that is located approximately 2 miles from the Las Vegas Strip. Slides were analyzed by microscopy at 400X magnification.  Airborne concentrations were analyzed for tree, weed and grass pollen and reported according to the criteria of the National Allergy Bureau (NAB).


Fraxinus, followed by Morus, Platanus, and Olea were observed in early and late February, March and early April, respectively, defining the duration of the tree pollen season. In March, Morus and Platanus were the dominant genera peaking at 10,781 and 1,987 grains/m3, respectively, considerably higher than the NAB very high level. A bimodal distribution was observed in weed pollen.  Ambrosia dominated the first mode in April, peaking at 71 grains/m3. The second mode in September was led by Chenopodiaceae/Amaranthaceae, peaking at 60 grains/m3, followed by Artemisia and Ambrosia. Grass pollen levels were lower but stable, resembling the distribution of weed pollen.

Conclusions :

The current pollen patterns mirror the historical trends. However, these data show earlier pollination and elevated Platanus pollen concentrations. These results highlight the importance of timely pollen forecasts to alleviate the burdens of allergy.