Trees are the earliest pollen producers, releasing their pollen as early as January in the Southern states and as late as May in the Northern states.

Trees can aggravate your allergy whether or not they are on your property since trees release large amounts of pollen that are distributed miles away from the original source.

Of the 50,000 different kinds of trees, less than 100 have been shown to cause allergies. Most allergies are specific to one type of tree, such as:

Catalpa
Elm
Hickory
Olive
Pecan
Sycamore
Walnut

The female of these species are totally pollen-free:

Ash
Box Elder
Cottonwood
Date Palm
Maple (Red)
Maple (Silver)
Phoenix Palm
Poplar
Willow

Some people with allergies to one species of tree show cross-reactions with other trees, especially in the alder, beech, birch and oak family, as well as the juniper and cedar family.

Preventive Strategies:

If you buy trees for your yard, look for species that do not aggravate allergies, such as crape myrtle, dogwood, fir, palm, pear, plum, redbud and redwood trees. You could also buy the cultivated female variety of ash, box elder, cottonwood, maple, palm, poplar or willow trees.
Avoid the outdoors between 5 - 10 a.m. Save outside activities for later afternoon or after a heavy rain, when pollen levels are lower.
Keep windows in your home and car closed to lower exposure to pollen. To keep cool, use air conditioners and avoid using window and attic fans.
Be aware that pollen can be transported indoors on people and pets.
Dry your clothes in an automatic dryer rather than hanging them outside, where pollen can collect on clothing and be carried indoors.

RELATED: Grass Pollen Allergies · Outdoor Mold Allergies · Ragweed Pollen Allergies

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