Seasonal Outdoor Allergy Triggers
What is pollen? Pollens are the tiny, egg-shaped male cells of flowering plants. Plants that are wind pollinated are often the cause of allergic rhinitis (hay fever), conjunctivitis (itchy eyes), and asthma. Pollens from spring trees, grasses, weeds and ragweed cause significant allergic reactions.
Plants which are INSECT-pollinated, such as azaleas and roses, are usually NOT an important cause of allergies.
Each plant has a period of pollination that does not vary greatly from year to year. Weather conditions can affect the amount of pollen in the air at any given time. Most plants release their pollen in the early morning hours. Pollens are small and can be carried for miles in the wind. Allergy symptoms are often minimal on days that are rainy, cloudy or windless. Pollen counts can be obtained from your local weather forecasters and from the American Academy of Allergy, Asthma and Immunology at www.aaaai.org/nab.
If you are allergic to the plants in your area, some people believe that moving to another area of the country with different plants will help lessen their symptoms. Many of the plants (especially grasses) and molds are common to most plant zones in the US. Additionally, other related plants can also trigger the same symptoms. Many who move acquire new airborne allergies within 1-2 years of moving. Moving is therefore not helpful.
It is very difficult to avoid pollens. Your doctor or nurse can tell you the time of the year to expect the individual pollens to be present.
To reduce your exposure to pollen:
- Do a thorough spring cleaning-windows, book shelves and air conditioning vents collect dust and mold throughout the winter and can provoke allergy symptoms.
- Reduce outdoor activity when pollen counts are high. Peak pollen times are usually between 5 a.m. and 10 a.m. It is better to plan activities after rain.
- Take medications at least 30 minutes prior to outdoor activity. Consult with your doctor to determine which medications are right for you.
- Keep home and automobile windows closed. Run air conditioners to filter the air. Open windows and fans draw the pollen inside.
- Shower and shampoo your child’s hair after outdoor activities before bed-pollen can collect on your hair and skin.
- Dry laundry in dryer during pollen season. Avoid hanging clothes outside.
- Keep pets off furniture and out of bedroom. Pollen can cling to the dog or cat after being outside.
- If you have a grass lawn, have someone else do the mowing. If you must mow the lawn yourself, wear a mask.
- Keep grass cut short.
Seasonal patterns in Southeast Virginia
Most trees pollinate in February through May.
Examples of relevant trees in our area and their pollination periods are listed below.
- Alder - January - April
- American Beech - April through May
- American Elm - Late winter to early spring and August-October
- Box Elder – March - May
- Cedar - Late winter to early spring
- Eastern Cottonwood – March-May
- Hickory – March- May
- Juniper – December – January
- Mulberry – April- May
- Pecan – March – April
- Poplar – April through May
- Red Birch – February – May
- Red Maple – February – April
- Red Oak – March – June
- Sweet Gum – March- May
- Sycamore – April - May
- VA Live Oak – February – May
- Walnut – April – June
- White Ash – March through May
As with tree pollen, grass pollen is regional as well as seasonal. In addition, grass pollen levels can be affected by temperature, time of day and rain. Grass pollinates from mid-April through September depending on which grass. Of the 1,200 species of grass that grow in North America, only a small percentage of these cause allergies. The most common grasses that can cause allergies are:
- Bermuda grass
- Johnson grass
- Kentucky bluegrass
- Orchard grass
- Sweet vernal grass
- Timothy grass
During the late summer and early fall, weed pollens do most of their damage to pollen allergy sufferers. Allergic rhinitis and asthma attacks are frequently caused by ragweed, cocklebur, and pigweed, Lambs Quarter, Dock, Marsh Elder, Mugwort, Plantain, Sorrel, Nettle and Goldenrod.
Ragweed pollination occurs nearly the same time each year and lasts between six and eight weeks. In the United States, the season ranges from mid-August through November or until the first frost. Ragweed is an important source of weed allergen in Virginia.
Lambs quarter is a large family of weeds and bushes with tiny, inconspicuous flowers, mostly concentrated in clusters. They colonize mainly waste land, acres, and very often salty soils. They are important in late summer and fall. Plantain and Sorrel are pollens that begin in April and continue into summer.
This information is not intended to substitute or replace the professional medical advice you receive from your child's physician. The content provided on this page is for informational purposes only, and was not designed to diagnose or treat a health problem or disease. Please consult your child's physician with any questions or concerns you may have regarding a medical condition.