I’ve got some not so good news for those of you with seasonal fall allergies. A study by the U.S. Department of Agriculture and others indicates that ragweed pollen season over the past 30 years has gotten longer. For example in Madison, it’s about 12 days longer, Minneapolis, 16 days longer, to as much as 28 days longer in Winnipeg. The main driving force behind this is believed to be a warming climate. Average dates of killing freezes have been pushed back as the climate changes. While a hard freeze in fall reduces pollen production significantly, it usually doesn’t disappear until a good snow cover has developed. The average dates of continuous snow on the ground has also slipped later into the year extending the allergy season. Interestingly enough though, the length of ragweed pollen season has actually shrunk in southern locations like Texas, Oklahoma, and Arkansas. While no definitive reason is given, maybe it’s getting too hot there for ragweed to stay healthy deep into the fall. Or perhaps it matures earlier in the season and then shrivels up in the fall. By the way, a ragweed plant can produce up to 1 billion pollen grains.
The American Academy of Allergy, Asthma, and Immunology (AAAAI) says about 12 million Americans are impacted by fall allergies. Besides ragweed, dust mites and mold come into play. Of course areas that have had a wetter summer and higher humidity will have more mold problems. They say in general a warmer climate causes plants to produce more pollen than they used too. This is accentuated by the increasing levels of carbon dioxide in the atmosphere now. Of course plants use CO2 and sunlight to produce energy. CO2 allows plants to produce not only more pollen, but more intense pollen. As such there are more allergens per grain of pollen than years ago in many species.
The AAAAI also suggests that easting a plethora of fresh fruit can enhance allergic reactions in some people. The different varieties of pollens mixing together in your body can confuse the body’s immune system. They say though, don’t stop eating fresh fruits. The health benefits outweigh the possible side-effects.
Well, good luck if you are going through that annoying routine of sneezing, runny eyes and nose, and itchy throat right now. I feel for you, as I get hit some as well. Just keep thinking cold thoughts like hard frost, and snow!