ragweed

Ragweed isn't a flower you'd pick for a bouquet - it's a common, often pesky plant known for releasing pollen that causes seasonal allergies. If you dread the fall and get itchy eyes and a runny nose around August or September, chances are this plant is to blame. It thrives in disturbed areas like fields, roadsides, and gardens.

Think of those hazy, golden days of late summer, often accompanied by sneezing fits. This plant is often the culprit. While it provides food for some wildlife, most people see it as a nuisance. It's not typically grown on purpose - it just appears.

Ragweed refers to several species of plants in the Ambrosia genus, but when people say "ragweed," they're usually talking about common ragweed (Ambrosia artemisiifolia). This plant is a summer annual weed native to North America. It has deeply divided leaves and small greenish flowers that are not pollinated by insects. Instead, it relies on the wind to carry its pollen.

And that's the problem. Ragweed produces an enormous amount of lightweight pollen, which travels easily through the air. This is why it's a major trigger for hay fever, also called allergic rhinitis, in millions of people each year. Symptoms include sneezing, itchy eyes, a runny nose, and congestion.

Ragweed isn't entirely without value. It provides food for birds and insects, and its seeds are eaten by some wildlife. However, for people with allergies, it's a plant best avoided. Farmers often try to control ragweed in fields, and gardeners pull it out of their flowerbeds.

Historically, ragweed was sometimes used medicinally by Native Americans, but its main claim to fame - or infamy - is as a major cause of autumn allergies. So the next time you feel a sneeze coming on in late summer or fall, remember the plain-looking plant quietly releasing its pollen into the air: it's likely ragweed at work.