Was there ever a more capable foe
Than one who shields his strength so?
An unremarkable plant, heavy with seed
cast to the wind with resolve and speed.
As his fecundity causes grief both far and wide,
from behind fairer bloom, he shrinks to hide.
Between sniffles, I must confess a grudging admiration for the homely Ambrosia artemisiifolia, that bane of autumn that we know as common ragweed. That’s why I even wrote the little verse above in its honour.
As a dabbler in the garden, I’m hard-pressed to think of another annual that can release up to a billion grains of pollen from just one solitary plant. Not that ragweed is ever terribly alone, growing in abundance as it does throughout central and eastern North America from the Southern states far up into most of Canada.
One North Dakota agronomist estimates that in the United States alone, 250,000 tons of ragweed pollen is released into the air in a year; tiny seeds that can journey up to 600 kilometres to find the right nose to pester.
Ragweed is an able adversary, which makes its mark on millions of lives. Consider the allergy industry this inelegant weed has spawned: the teams of scientists trying to create the better pill or spray to stem the flow of the sinuses, the weeping eyes, the bleary-headedness and the sleeplessness; all the pharmacies selling the medications to business people who claw at itchy eyes and whose children will spend the fall giving the “allergic salute” – that palm up swipe of the nose.
Think, too, of the enormous costs to the economy in sick days when the allergy symptoms get too bad to bear. It’s all thanks to this non-descript procreating machine with its beady little flowers.
Where I live in southern Ontario, July was uncharacteristically hot and sticky; the begonias melted, the cone flowers keeled and the rose bushes simply refused to share their usual abundance of blooms.
But Ambrosia artemisiifolia and its taller and almost as virile cousin Ambrosia trifida (giant ragweed), are not that precious. These hardy, rough boys love nothing more than to sprout up in vacant lots and alongside highways and railroad tracks. As some of us cultivate, fertilize and cajole our gardens, they’ll take root in any patch of dirt.
At least giant ragweed grows tall enough (up to four metres) to notice. Common ragweed is often overlooked in fields and parks. Showier plants, such as goldenrod, are mistaken for ragweed, maligned and uprooted, while the real culprit stands off to the side or, more likely, down at the local vacant lot – like a teenager up to no good. “Inconspicuous” is the adjective botanists usually employ to describe common ragweed’s gray-green branches, leaves and greenish-yellow flowers. And so it goes – and grows – unnoticed and building toward a crescendo of airborne misery that only ends with the frost.
Our adversary is a survivor without peer. Its seeds can lay dormant for up to 40 years and still germinate if disturbed. Crop farmers in the United States are reporting that both common and giant ragweed are becoming resistant to glyphosate, considered the king of the herbicides. And there are stories of ragweed springing forth through newly laid asphalt or concrete. Like a creature from science fiction, ragweed just keeps on coming.
The scientists say that the heat and scorching sun created conditions for a banner year for ragweed in much of North America. But as you sneeze and curse the dratted weed, wondering how one miserable pest of a plant can cause you so much grief, pause and think again. You’re not just fighting your allergies, you’re battling a feat of science, a dastardly little marvel of genetic engineering.
First published in Allergic Living magazine. To subscribe or order a single issue, click here.