AHSC logo Allergy and Asthma in the
Southwestern United States
Information for patients with allergy and related problems
in the Southwest

Tucson Pollen Today and Tomorrow - September

Pollen and mold counts are increasing.  Carelessweed (Amaranthus palmeri) and Russian Thistle (Salsola) are flowering already. This year Carelessweed and Canyon Ragweed (Ambrosia ambrosiodes) are both growing very fast in low lying areas and washes because of the unusually wet monsoon, predictive of a severe hay fever season this fall.  The important ragweed Ambrosia deltoidea (triangle leaf bursage, rabbit bush) is not flowering at this time. Grasses have also been growing and flowering for two months and will become a major contributor to atmospheric pollen.  Bermuda grass (Cynodon dactylon) established in alleys and roadsides has greened up and has been releasing pollen. Pennisetum ciliare (Buffel Grass) is flowering, particularly at county roadsides.    Other grasses such as Pennisetum setaceum (Fountain Grass) and Eragrostis Lehmanniana (Lovegrass), are growing and flowering now.  The warm soil and higher humidity is causing mold growth, and airborne spores will become a problem for many asthmatics after the monsoon is over and the surface layers of soil begin to dry up.

Note:  This information is based on ongoing observation of flowering allergenic plants in the Tucson metropolitan area, and not on pollen counts.   Appearance and persistence in the air of any particular species of airborne pollen are expected to be later than the onset and duration of flowering of the plant of origin.                                                             Back


Disclaimer:   This site is for educational purposes only.  Any information that you have found in this web site is not intended to replace medical care or advice given to you by your own physicians. You should consider consulting your local medical library and other web sites for additional information. 

Comments and suggestions welcome!   Email: schumach@u.arizona.edu
Content Owner:  Michael J. Schumacher, MB, FRACP, The University of Arizona
Updated 8-29-2012