While many people look forward to getting out in the warm spring weather after hibernating through the winter, allergy sufferers dread the sneezes, burning eyes and headaches spring tows in its wake. Trees with ornamental blooms look especially suspicious. Masses of tiny white flowers cover Bradford pears — Pyrus calleryana "Bradford" — in early spring, but this tree isn't usually a culprit in pollen allergies.
Identification
Bradford pears are a member of the Callery pear family, a strictly ornamental cousin to Bartlett or D'Anjou pear trees. They quickly produce a rounded, symmetrical crown that remains tidy without pruning and sport oval, glossy green leaves that are among the last to change in the fall. Landscapers once heavily planted this tree, in fact, due to the late fall shades of fiery orange or red, the neat habit and the spring flowers. Unfortunately, the tree quickly earned the nickname "Fatford pear" due to its wide, sidewalk-blocking growth. It also has a weak structure — major limbs of older trees often snap in windy weather.
Scent
Bradford pears bloom in April to May for most zones, and the masses of white blossoms often remain on the tree until the leaves appear. The scent is heavy and, to many, malodorous -- a kinder way of stating that the smell is repulsive. If you smell a Bradford pear, don't assume it's the cause of your sneezing. Volatile oils produce the carrying scent, not pollen. Higher temperatures evaporate more oil and make the stench worse, but it won't affect your allergies.
Pollen
Spring winds carry lighter pollen grains from trees to your nose, and the pollen may swirl around your neighborhood for months. Bradford pears, however, produce heavy, sticky pollen that is not easily wind-blown. Incredibly, that's why they also produce such a rotten stench -- they attract flies to carry the pollen rather than thinly-stretched bees. Because of the pollen's weight, it's not likely the instigator in your spring allergies. In fact, a 2010 allergy study tracked tree pollen in the Washington, D.C. area for more than 10 years and reported no rogue pear tree pollen.
Coping
The trees with the most inconspicuous flowers often produce the worst allergies. To add insult to injury, most modern landscape trees are pollen-producing male cultivars, planted in an effort to avoid messy fruit or seed pods. Ash, elm, oak, maple and juniper are likely allergy suspects. Ask your local allergist about problem trees in your area, and have your medication on-hand to coincide with their bloom times. Keep your windows closed, change your clothing after working outdoors and splurge on a high-quality air filter. And wipe down Fido: pets often carry pollen indoors.
References
- University of Connecticut; Pyrus calleryana
- North Carolina State University Cooperative Extension; Gardening Q & A; Rett Davis; March 2000
- Dr. Neil Kao Allergy and Asthma Website; Does the Pollen from Bradford Pears...; Neil Kao; 2010
- PubMed: Pollen Aeroallergens in the Washington, DC, Metropolitan Area
