How do pollen counts work?

April 19th, 2011

Most pollen counts are obtained using a volumetric device–a method by which number of pollen grains (or mold spores) are measured in a defined volume of air. At our office, we use a Rotorod system, which captures grains on a small rod that spins at a known rate at a defined interval. The pollen is transferred to a microscope slide, then grains are counted and categorized by our research coordinator (Andrea) as trees, grasses, or weeds. Although we are able to differentiate species based on pollen grain morphology (appearance under the microscope), we typically report the counts as a category rather than a species.
When grass season starts, the slide comes to life with beautiful oval grains that sometimes fill the entire microscopic field!
Pollen counts on other websites are typically made at other physical sites, i.e. Eugene, Portland, or Bend. We are currently the only pollen counting site in Southern Oregon. We make our counts available to news outlets (Channel 12 KDRV 6pm news) and tweet/post online (see front page of this site).

Kevin Parks MD

Spring pollen 2011

April 19th, 2011

As you can see by our pollen counts, the weather is a key factor influencing anemophilous (wind pollinating) plants in the Rogue Valley. So far, our spring has been wetter than average, and tree pollen has been significant during the few “sunny” and windy days since February. In years past, we’ve observed large grass counts after wet early spring seasons, but time and weather will tell how big the upcoming grass season will be… but it will come! Check out Facebook or Twitter feeds on the lower right side of our front page for daily pollen counts through weed season (mid summer).

Kevin Parks MD