My pictures of ragweed will help you identify a plant that many people speak of, even though they don't know for sure what it looks like. The reason that the weed comes up in conversation and in the news so frequently is that it is the prime source of fall allergies in North America. But why do people have so much trouble identifying a plant that has such a powerful impact on the populace?
Well, it's understandable that beginners in plant identification would have a problem identifying this weed. Look at the picture on this page, which provides a bird's-eye view of common ragweed. It is about as nondescript a weed as you will find in the plant world. There are no colorful berries on it as there are on, for example, bittersweet nightshade. Even when in bloom, its flowers can only dream of owning the character of dandelion's flowers.
But problems with identification are not limited to novices. I once went on an August wildflower walk with a woman (let's call her Wildflower Wilma) who was about as well-versed in the flora of this particular locale as anyone could be. She rattled off plant name after plant name on this tour, with the assurance of someone who was thoroughly at home in the woods. But I must admit that I was somewhat taken aback when, toward the end of the walk, Wildflower Wilma held up a mugwort plant (Artemisia vulgaris) and confidently identified it as "ragweed."
Nobody knows everything, of course. And upon further reflection, I was able to sympathize with her, to some degree, in her misidentification: if any plant can challenge ragweed for the title of Least Distinctive Weed, it's mugwort. Perhaps it's also worth noting that the botanical name of common ragweed is Ambrosia artemisiifolia. Its specific epithet is an indication that folks have noticed a resemblance between it and some members of the genus, Artemisia (for example, Silver Mound artemisia), to which mugwort belongs.
My hope is that, after viewing my pictures of ragweed on these seven pages, you'll be able to do something that even Wildflower Wilma could not do: namely, identify, beyond all doubt, a weed that has brought misery to untold millions of allergy sufferers. On Page 2 we'll begin with a closeup of the plant's leaflet....