Every year in the late summer and early fall, allergy sufferers begin blaming goldenrod (Solidago sp.) for causing hay fever. Talk about a bum rap!

The real culprit is ragweed, said Andrea DeLong-Amaya, director of horticulture at the Lady Bird Johnson Wildflower Center at the University of Texas at Austin. Then why do so many people blame goldenrod for causing sneezing, a runny nose, itchy eyes and trouble sleeping?

DeLong-Amaya believes it’s because goldenrod’s attractive horizontal displays of brilliant yellow flowers make it by far the showier of the two plants when they are in bloom. “People see the flowers of goldenrod,” she said.

RagweedRagweed (at right) blooms at the same time but, DeLong-Amaya said, people really don’t see those flowers, which are green or white, not showy and presented in small heads.

If you still need convincing to let goldenrod off the hay fever hook, consider this more scientific explanation.

To get an allergy from a plant, the pollen from the plant’s flowers have to get into your nose. That’s not possible with goldenrod, DeLong-Amaya said.

“Goldenrod pollen grains are heavy, too heavy to float in the air and get up your nose,” she said. “Goldenrod is pollinated by insect couriers such as bees and butterflies that transport its pollen from one plant to another.”

Ragweed, on the other hand, relies on airborne pollination, which DeLong-Amaya calls a crapshoot. Airborne pollination occurs when the flower spews vast amounts of very light pollen into the air. Once airborne, the tiny pollen particles drift on wind currents until they eventually land ... somewhere.

“Plants that pollinate in this manner have to produce a lot of pollen because only a small percentage will land on a flower of the same kind and pollinate it,” she said.

Monarch on goldenrod“Plants like goldenrod that are insect pollinated don’t have to produce as much pollen as plants that rely on airborne pollination,” DeLong-Amaya said. Insects, she pointed out, have a much better chance of carrying pollen to the right plant than the wind does.

If you are one of the 10 to 20 percent of Americans the Asthma and Allergy Foundation of America says suffer from hay fever, one way to head off misery in late summer and fall is to remove ragweed before its flowers and can do any nasty work. The trick in successfully doing that is to be able to identify goldenrod and ragweed by the leaves.

“Goldenrod has a smooth lanceolate leaf, whereas ragweed has a dissected leaf similar to a marigold,” said Amanda Bennett, manager of display gardens at the Atlanta Botanical Garden. Once you learn to make a positive identification, the shallow-rooted plants are easy to hoe or dig up.

Aster and goldenrodA Cherokee legend about how goldenrod’s yellow flowers got their brilliant color is far less scientific. According to Ila Hatter, an interpretive naturalist in Bryson City, North Carolina, who teaches the historical uses and folklore of plants, the story involves two Indian girls who were away from their village foraging for wild food plants. One girl was dressed in yellow; the other, in lavender. When they returned to the village, it was being attacked by an enemy. Terrified, they ran into the woods crying out to be saved. The attacking warriors ran into the woods looking for the girls, but a medicine woman found them first. She took pity on them and poured magic over them. When the warriors arrived at the place where the girls encountered the medicine woman, all they found were the flowers of goldenrod and aster.

Even if you don’t believe in legends and folklore, perhaps the scientific information will help you look at the beautiful flowers of goldenrod with a more understanding and forgiving eye.

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Inset photos: (ragweed; goldenrod with monarch) Dendroica cerulean/Flickr; (aster and goldenrod) jar/Flickr