April 12, 2010
Mary Ann Andersen
If misery loves company, then hay-fever sufferers should never have to be alone.
Thirty-five million Americans have pollen allergies that may cause itchy eyes, ears, and throats; difficulty breathing; or all of the above.
Which Plants Cause Allergies?
- Insect-pollinated plants have bright flowers and heavy, sticky, pollen grains that tend to stay put and cause few allergies.
- It’s the wind-pollinated plants that cause the most problems for allergy sufferers. Their small, dull, inconspicuous flowers produce clouds of tiny, light, pollen grains that are blown aloft for great distances and can easily penetrate window screens.
- To increase the chances that at least some pollen grains will reach the appropriate female flowers, plants produce many more grains than are needed—and some end up on our hair, on our clothes, and, alas, in our eyes and nasal passages.
The Big Offenders
Pollen counts are high in the spring and fall. Trees, grasses, and weeds are responsible for most windblown pollen. The big offenders are:
- Large shade trees such as oaks, maples, and beeches; tree pollen emerges in the spring.
- Most lawn grasses; grass pollen emerges in the spring and continues through summer.
- Common weeds such as lamb’s-quarter, pigweed, and ragweed, which may produce a million pollen grains on just one plant. Some weed pollen begins in the summer; ragweed, a major allergen, causes problems in late summer and fall.
- Goldenrod, which blooms along with ragweed, is often blamed for allergies, but it is bee-pollinated and causes few problems.
There has been a huge increase in hay-fever sufferers in recent years, partly due to a growing interest in fruitless and seedless “litter-free” trees. Many of these are males that may be litter-free, but they are definitely not pollen-free. To make matters worse, fewer female trees are being planted, so less pollen is being caught. Instead, it falls to the ground, where it can be stirred up by mowers and foot traffic.
How to Limit Allergy Discomfort
For gardeners or anyone who has allergies but loves the outdoors, there are steps that can be taken to limit discomfort.
- Plan your outdoor activities when pollen counts are lowest, such as in the late afternoon or during cool, wet weather.
- Be especially wary during the morning, when pollen is often emitted in larger amounts.
- Dry, windy days distribute pollen farther, whereas rain washes it from the air, lowing pollen counts (but encouraging mold, which causes some people more headaches).
- Plant only all-female trees and shrubs.
- Limit grassy areas by planting insect-pollinated ground covers.
By carefully choosing the right plants and gardening when pollen counts are low, you can make your yard a healthier and more enjoyable place to be, which is nothing to sneeze at.