Pollen Collection Date - August 14th, 2017



  • Chenopod pollens (which includes Kochia, Russian Thistle, Lambs Quarter and Careless Weed) are on the rise. On dry days we will be seeing high levels of these weed pollens over the next 4 weeks. Sage is just starting. 
  • Outdoor molds remain high, including the usual Cladosporium and Alternaria (pictured below), but also Curvularia, Bipolaris and several other Ascomycete spores.
  • Grass pollen levels have decreased from their peak but still holding steady at low to moderate levels.
  • Tree pollen is done for the year. 
David R. Scott, MD
Allergy & Immunology

Left (8/2017) - Alternaria mold with a few scatter Curvularia. Altenaria has been called the "house dust mite of the West" because it is such a potent driver of respiratory symptoms in Southwestern United States. It blows on warm dry days and causes symptoms not just by inducing an allergic response, but also stimulates our "innate immune response," which is a fascinating new area of research being carried out by one of my former mentor's, Dr. Doherty (https://www.ncbi.nlm.nih.gov/pubmed/24296722). 

Willow growing along Mesa Creek near Powderhorn photographed May 7th, 2017. Tree pollen in Grand Junction, Delta and Montrose is mostly done releasing for the year, but the high country continues to deliver. Willow and even a little late-pollinating Scrub Oak and Juniper release and blow down to lower elevations though May and early June. 

An interesting appearing Mormon tea pollen granule. We found several of these scattered on our 4/25/17 collection. We don't usually test to Mormon tea, but if we keep seeing it,then we might add this species to our panel for late Spring allergy sufferers. 

Ash tree 3/26/17, one of the first ash trees I've noticed this season to release its pollen. We are still seeing only minimal ash on our pollen counter. 

Aspen tree pollen is released in early to mid March, around the same time as other members of the Populus genus, including Cottonwood and Poplar. 

Ornamental Juniper, as seen here on March 19th, is a common source of pollen throughout March in the Grand Valley. Native Juniper will pollinate in the higher country later in March and into April. 

The pollen sample from Feb 24th was full of Siberian Elm. We were interested to see a few Juniper (looks like a fried egg in the middle) and Maple pollen mixed in. 

We picked this small Siberian Elm branch near the allergy clinic in Grand Junction on Feb 15th, 2017. Small buds releasing pollen can be appreciated. Visible pollen could be seen with flicking of the branch. 

On the left is chenopod weed pollen from our Sep 8th sample, which is one of the Grand Valley's worst fall pollens. The chenopod pollens include Kochia, Russian Thistle, Lambs Quarter and Careless Weed. These share a high degree of allergic cross reactivity (ie - if you're allergic to one, you're likely allergic to the other) and look nearly identical under the microscope. 

On the right is sage pollen from our Sep 1st sample. Sage is the Grand Valley's most robust fall weed pollen, often pollinating well into November. 

On the left is ragweed pollen with mold in the background from our July 28th sample. Unlike most other places in the United States, the Grand Valley grows relatively little ragweed. Our most significant pollens this time of year are the Chenopod family of weed pollens, including Kochia, Russian Thistle and Lamb's Quarter. 

(Above) Grass pollen surrounded by various types of mold spores from our June 24th sample. 

Here you can see local grass pollen in action. This video was captured May 30th, 2016, from the bank of the Colorado River near downtown Grand Junction. 

Oak pollen from May 19th. This likely originated from scrub oak, blowing all of the way from the Grand Mesa or Uncompahgre Plateau to downtown Grand Junction.

Some of the first grass pollen of the year that showed up May 3rd, 2016. Earlier than we had expected!
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