Trees are the earliest pollen producers, releasing their pollen as early as January in the Southern states and as late as May or June 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 can be distributed miles away from the originial 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: ash box elder cottonwood elm hickory maple olive pecan poplar sycamore walnut willow However, people do show cross-reactivity among trees in the alder, beech, birch and oak family, and the juniper and cedar family.

If you buy trees for your yard, look for species that do not aggravate allergies such as catalpa, crape myrtle, dogwood, fig, fir, palm, pear, plum, redbud and redwood trees. Avoid the outdoors between 5-10 am. Save outside activities for late 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 also be transported indoors on people and pets. Dry your clothes in an automatic dryer rather than hanging them outside. Otherwise pollen can collect on clothing and be carried indoors.