On the Lookout for Elm Pollen: An Elm Pollen Adventure

What's up, Forsyth? It's time for another pollen blog post from a guest writer and expert with the Allergy and Asthma Center NC. 

On the Lookout for Elm Pollen: An Elm Pollen Adventure

Written by Anne Ambs, Allergy and Asthma Center of NC, Cone Health Medical Group

Hi, I’m Anne, nurse practitioner at the Allergy and Asthma Center of NC! As a nature enthusiast, I can be found hiking and exploring everything outside in North Carolina on most weekends. While soaking in Nature’s beauty this past weekend, I went on a short quest to find elm trees in the Pilot Mountain area, as elm pollen will soon make an appearance in the environment. While I did not spot any elm trees on my outdoor adventure this weekend, my eyes and nose were itching to tell a different story, that they had, indeed, already arrived. 

Elm trees belong to the Ulmus genus, and they live primarily in North America, Europe, and parts of Asia. Interestingly, elms can be found in every US state except Alaska, Colorado, Hawaii, Montana, and Wyoming. Encompassing approximately thirty species, elm trees have 2 distinct flowering and pollinating seasons, with elm trees in Southern United States generally pollinating from January through April. However, some southern elms flower and pollinate late into the summer with some seasons lasting into November. In the summer, elm trees display green, oval-shaped leaves with a saw tooth edge, grayish-brown bark with deep, rough furrows running lengthwise, and leaves that are arranged alternately on their long, graceful branches. Typical of deciduous trees, the elm leaves turn golden yellow or brown in the fall before shedding their leaves and becoming dormant over the winter.  

Historically, elm trees have been thought to symbolize strength and resilience, serve as gathering places, and strengthen bonds within a community. Today, elm trees continue to provide benefits including offering habitats for birds and other small animals which helps to strengthen diversity, reducing air pollution by absorbing carbon dioxide and other air pollutants while producing oxygen, providing shade and temperature moderation, and retaining water in soil which protects against erosion and may decrease damage due to flooding.  

Unfortunately for pollen allergy sufferers, elm tree pollen is necessary for propagation of the species. Elm trees are monoecious, meaning that they contain both male and female flowers. Pollen is released by the male flowers of the elm tree and carried by the wind to the female flowers of either the same or a different tree. Elm pollen particles are yellow/green in color and their small and light structure allows them to be easily carried by the wind. They roughly measure between 20-30 micrometers in diameter and cannot be seen without a microscope. 

Image 1 (taken by Forsyth County staff on February 24, 2025): Three elm pollen grains shown under a microscope at 40x magnification. The pink color is from a dye called Calberla’s stain that is used to make pollen grains easier to see for counting and identification.  

 

While elm trees have many benefits, they can cause havoc for people affected by pollen allergies during times of pollination. Symptoms include sneezing, nasal congestion, runny nose, watery and itchy eyes, itching in the throat, and wheezing. The pollen produced in the fall typically produces more severe or bothersome allergy symptoms.  Any time you find your allergy symptoms are correlating with high pollen counts, you might consider seeking an assessment and guidance from a health care provider for possible causes and treatment options.