Grass Pollen
Only about 20 of the 1,200 or so species of grass in North America cause allergic reactions. The most common are Perennial Rye, Bermuda, Redtop, Fescue, Salt grass, Johnson, Sweet Vernal, June and Timothy.

If one or more of these grasses is in your lawn, consider choosing other varieties of grass to ease your allergies. Keep the grass mowed short to prevent seeds. It may be best to have someone else mow your lawn.

If you decide to do the mowing yourself, wear a mask to cut down your exposure to the pollen. Mow shortly after a rain or later in the day (when pollen concentrations are lowest) and when there is little breeze (since grasses rely on the wind to spread their pollen). Once you’re done, leave your shoes at the door. Shower and change your clothes immediately to reduce your contact with clinging pollen.

Tree Pollen
There are 650 trees native to the US; the pollens of about 100 are allergens. The most common offenders are Alder, Ash, Beech, Birch, Chestnut, Cypress, Japanese Cedar, Western Red Cedar, Elm, Hazel, Heath, Hickory, Maple, Myrtle, Mulberry, Oak, Olive, Pine, Plane, Poplar, Ti, Wattle, Walnut and Willow.

When planting trees in your yard, choose from the varieties that don’t cause allergies, like Catalpa, Crape Myrtle, Dogwood, Fig, Fir, Palm, Pear, Plum, Redbud and Redwood trees. To minimize your allergies, keep your windows tightly closed and use your air conditioner while the trees are blooming.

Ragweed
This tenacious weed is named for the ragged shape of its leaves. It begins pollinating in late summer, around mid-August, and continues until a heavy frost. Its pollen is wide-reaching and productive—a single plant can produce a billion grains during its growing season and grains have been found 400 miles out to sea and up to two miles in the air.

Seventy-five percent of people who are allergic to pollen are allergic to ragweed. If you’re sensitive to ragweed, you may also get symptoms from cantaloupe, banana, chamomile tea, sunflower seeds and some types of honey.