Against Pollen Allergies
Many people suffer from allergies both mild and severe, with ragweed specifically and pollen in general at the top of the list. Selecting plants at home that do not generate pollen is an effective preventive strategy in many cases, but airborne wind-carried pollen respects neither lot lines nor municipal borders, so it will likely drift in anyway. Local governments have their own criteria for landscaping priorities, and the wilderness runs its own course. Yet there are many actions we can take to both reduce or eliminate pollen sources around our home exteriors and also reduce encountering pollen in our daily routine.
Plants, like animals, have distinct male and female aspects. Males produce pollen to fertilize the female ovules. Ovules form seeds which, like eggs, contain the nutrients necessary for the development of the embryonic plant. Plants reproduce by pollination, in which pollen grains are transferred from one plant to another. Pollen can be transported by insects such as bees or by the wind. Most cultivated plants with showy flowers are entomophilous (pollinated by insects) and do not cause pollen allergies because their pollen is sticky, not airborne. These plants attract insects with nectar-containing flowers.
Trees, grass and ragweed are major sources of pollen and its resulting allergies in the U.S. Trees can aggravate allergies whether or not they are on our property because they release large amounts of pollen that can be distributed miles away from the original source. Trees are the earliest pollen producers, releasing their pollen as early as January in southern states and as late as May or June in northern states.
Most allergies are specific to one type of tree, although some people show cross-reactivity among trees in the alder, beech, birch and oak families, and also in the juniper and cedar families. Trees that typically do not cause allergies include female ash, red maple, yellow poplar, dogwood,magnolia, double-flowered cherry,fir, spruce and flowering plum.
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. Of the 1,200 species of grass that grow in North America, only a small percentage cause allergies. The most common grasses that can cause allergies are Bermuda grass, Johnson grass, Kentucky bluegrass, orchard grass, sweet vernal grass and Timothy grass.
Ragweed and other common weeds such as curly dock, lambs quarters, pigweed, plantain, sheep sorrel and sagebrush are some of the most prolific producers of pollen allergens. Although the ragweed pollen season in the Chicago area typically runs from early August to late September or early October, ragweed pollen levels usually peak around Labor Day. In addition, pollen counts are highest on dry, hot and windy days.
Ragweed pollen is notorious for causing allergic reactions, specifically allergic rhinitis. Up to half of all cases of pollen-related allergic rhinitis in North America are caused by ragweed, and climate change may be making it worse as higher temperatures creep northward. Ragweed is a public health concern as the percentage of people in the U.S. affected by hay fever (allergic rhinitis) from ragweed is around 15 percent, comprising the most frequent allergic response in the nation. In addition to taking preventive measures at home, those suffering from seasonal allergy symptoms should seek medical advice and treatment from a medical professional when necessary.
Prevention against the adverse impact of pollen includes implementation of physical measures and adoption of protective behavior. As with all allergens, the best solution is to avoid exposure to pollen; particularly for infants and those with asthma and eczema. Preventive steps vary depending on the severity of symptoms. Maintaining a pollen-free yard or garden might not be advisable to all but may be necessary to those with a strong reaction to pollen. While total exposure to pollen in unavoidable, its impact can be effectively mitigated to the point that allergic symptoms can often be avoided.
Chris Krofton is the founder and CEO of PPiA Homes LLC, a Chicago company that builds homes and communities that help to prevent and mitigate asthma, manage chronic pain, foster good sleep and cultivate wellness. For more information, call 312-436-2887 or visit PPiAHomes.com.
Allergy Prevention Steps During Pollen Season
- Design the home landscape without grass. Choose ground covers, bulbs and other herbaceous plants that don’t produce much pollen or that are pollinated by bees and insects, rather than the wind. Select trees that are pollen-free.
- Mow grass at a low height before it goes to seed.
- Get rid of ragweed around the property.
- To prevent pollen getting into the house with outside air, install removable mesh specifically designed for pollen in windows. Use a MERV 8 filter for mechanical ventilation such as energy recovery ventilator (ERV).
- Make sure that the heating and air conditioning system has allergen-rated filters for air that is recirculated inside the house.
- Keep home and car windows closed to lower exposure to pollen.
- Avoid the outdoors between 5 a.m. and 10 a.m., because levels of pollen tend to be highest during those hours.
- Wear an allergy mask when working, exercising or walking outside.
- Avoid exercising on days that it rains and just before or after thunderstorms.
- Pollen can also be brought indoors on people and pets. Shake pollen off from clothing outside the house and wash it separately. Remove shoes and clothing after mowing the lawn.
- Don’t dry laundry outside, where pollen grains can stick to fabrics.