When allergy season comes around, people begin to blame goldenrod for their hay fever, when in fact, this plant is completely innocent! The bloom of the flamboyant goldenrod just so happens to coincide with the flowering of ragweed, the true plant to blame.
Goldenrod vs. Ragweed:
Goldenrod is a highly beneficial native species of flower. Goldenrod has heavy grains of pollen, which have no other way of reaching another goldenrod flower except for the hard work of a pollinator. This plant completely relies on pollinators in order to reproduce, and in turn offers them a food source. The pollen from this flower has no way of reaching the human nose to cause allergies simply because it is too heavy to get there.
Ragweed, on the other hand, is a wind-pollinating plant, meaning that it’s pollen becomes air-borne and floats along the wind until it lands somewhere. Of course, the goal is to reach another ragweed plant and successfully reproduce, but this can be quite difficult due to the inaccuracy of wind-pollination. To make up for this, ragweed produces very high quantities of pollen, which irritate the noses of people with seasonal allergies.
Goldenrod, tends to shoulder the brunt of the blame for seasonal allergies, simply because it is visible. Below are photos of goldenrod and ragweed, and you can certainly see why goldenrod is the one that gets the bad rap.
Goldenrod, shown left, sports striking yellow flowers. The bright colouring is produced in order to attract insects to carry its pollen. Ragweed, shown right, blooms at the same time, but is barely noticeable. This is because ragweed has no incentive to spend energy on pigment; it doesn’t require the attention of any insect. Instead, it has small and discrete green flowerheads that release pollen.
When the plants are not flowering, they can be identified by their leaf structure. Goldenrod has narrow, horizontal, grass like leaves. Ragweed has fern-like leaves similar to marigolds.
Allergy-sufferers can safely grow goldenrod in their garden and have nothing to worry about if it is present near their home. Next time you see goldenrod, remember that it is not a pesky weed, but a beautiful flower that is beneficial to native pollinators.
By Christine Macpherson