America’s Trees of Allergies
Tree Pollen Allergy Tour: North East
New Jersey is definitely “pine land,” says Dr. Donald Dvorin, certified pollen counter and co-founder of The Asthma Center, an allergy clinic with nine locations in Pennsylvania and New Jersey.
Pine tree pollen can become so dense, says Dvorin, that “it almost looks like smoke is coming out of the trees” – so much so that people unfamiliar with the phenomenon have been known to call the fire department.
Although one grain of pine pollen is about 100 microns in size – far smaller than the head of a pin – it’s relatively large compared to other pollen, making it less likely to be windborne, and also less likely to get into your airways and lungs. That’s partly why some experts don’t believe that pine pollen is a common allergen.
Still, according to Dr. John Costa, medical director of allergy clinical practice at Brigham and Women’s Hospital in Boston, “If you live in an area surrounded by pine trees and that pine pollen is falling directly downward and landing on your car, your deck and your lawn furniture, and then you touch these things and put your finger near your eye or nose, it can cause problems.”
Watch out for Oak and Mulberry Pollen
Other top pollen-producing trees in New Jersey, New York and Pennsylvania, include juniper (no surprise there), elm (slippery elm, not the American variety that was all but wiped out by Dutch Elm Disease in past years), maple, birch, Sweetgums and cottonwood.
But the tree that produces the most pollen every year in the area is likely the tall stately oak.
“It’s in the top echelon of tree pollen production,” says Dvorin. It can produce anywhere from 1,000 to 3,000 pollen grains per cubic meter of air, which for one species, says Dvorin, is “tremendous.” (Experts say that, in most of the country, people become symptomatic when pollen counts are 200 per cubic meter and up.)
Thick yellow oak pollen is known to blanket the residential areas of Cherry Hill and Forked River, New Jersey.
“When you get a lot of windy weather, that’s when you see all the cars and roads coated, especially in the suburban residential areas,” says Dvorin. On those days, city workers get out the street cleaning machines, but that doesn’t do much to stem the symptoms of allergic residents, who, says Dvorin, “for the most part just grin and bear it.”
In New York City, male mulberry trees pose a significant allergy problem, according to Ogren. They line the streets in many neighborhoods, chosen by arborists and landscapers because they resist disease and insects, withstand smog and, like all male trees, produce no messy fruit or flowers.
However, it’s only the male trees that produce troublesome pollen, says Ogren, who is promoting a sex change in tree planting to help solve the mulberry pollen problem.
Next page: The Midwest’s most allergenic trees