Unless you have bees up your nose on a regular basis, don’t blame late-season allergies on goldenrod. However, if you do find bees in your schnozz, seek medical (and perhaps entomological) help immediately.
While most plants respond to the shrinking hours of daylight in the late summer by starting to wind down their business for the season, goldenrod is a “short-day” plant, the type that is stimulated to bloom by dwindling light. It is a perennial in the aster family, and is widespread across North America. Continent-wide, we have something on the order of 130 species of goldenrod in the genus Solidago.
As one of the most abundant blooms of late summer and autumn, this native wildflower is for many pollinators, including numerous bee species, a vital source of nectar and nutritious pollen. Unfortunately, this latter item has given goldenrod a black eye (but not a black-eyed Susan) among allergy sufferers.
Goldenrod’s showy yellow flowers are in full view along roadsides and in meadows and pastures at about the same time one of the more intense waves of seasonal hay fever typically begins.
So it’s understandable that goldenrod has been blamed for the red itchy eyes, sinus congestion, sneezing, and general histamine-soaked misery that many folks experience this time of year. But it turns out that goldenrod pollen is innocent of all charges. Goldenrod can’t be guilty because its pollen is heavy. That’s a relative term, I suppose, since it’s light enough that bees manage to cart away loads of it. But in the pollen realm it weighs a ton, and thus cannot blow far from the plant. It isn’t that goldenrod pollen is incapable of eliciting an allergic response; it’s just that to do so, something – a bee, for instance – would have to deliver it to your nasal passages.
So who is to blame for the spike in late summer allergies?
The culprit is goldenrod’s evil cousin, ragweed, which does not behave at all like its golden relative (I suspect that everyone has a family member or two like ragweed among their kin). Ragweed, which is also a native plant in the family Asteraceae, churns out loads of super-light pollen, quite the opposite
of what goldenrod does.
Ragweed pollen is so light that it can remain airborne for several days. In fact, large quantities have been found in the air as far as 650 kilometres out to sea. And a single ragweed plant can produce a billion pollen grains to fly on the breeze and make you sneeze. Yep, ragweed pollen is the stuff that stuffs you up. One reason we fail to suspect ragweed for inflaming our nasal mucosa is that its blossoms look nothing like proper flowers. They are a dull, drab green, the same colour as the plant. It’s as if ragweed is purposely trying to avoid attention, staying under the radar to let snazzy goldenrod take the rap.
Ragweed is easy to overlook because it’s wind-pollinated, and therefore has no need to advertise with bright colours and sweet nectar to attract pollinators. Insect-pollinated plants have to entice bees, butterflies and other couriers with flashy colours and tasty sweets. Wind-pollinated plants have discovered it’s much easier to attract the wind than bugs. The downside is that they need to make tons more pollen.
Most ragweed species – there are about 50 of them – are annual, but they come back each spring from the copious seeds produced each fall. Ragweed will continue to churn out allergens until the first hard frost, so let’s hope we don’t have an exceptionally long season this year.
Please help spread the word that goldenrod rules, and spare it further accusations.
Paul Hetzler writes about nature for The Saturday Evening Post.
He’s usually careful not to inhale bees.