"It's called smartweed," John Carroll told me one day while I was helping him maintain one of the flower beds he had planted in the old Minton Stable Garden. It earned that name, he explained, because it is smart enough to take on the appearance of a flower that one might grow on purpose. With its greenish-pink brush-like flowers and long tapered leaves, it does seem too attractive to pull, especially when it adds some color to a fading fall garden.
But don't be fooled. It may not strangle plant stems like bindweed does, but smartweed can still be invasive. Known by its scientific name of polygonum hydropiper, there are two main types of smartweed: aquatic and terrestrial. I've been encountering the terrestrial smartweed not only in my MSG plot, but also in my gardens at home, as you can see in a neglected flower bed next to my house (perhaps posting this photo will shame me into leaving my perch at the Ula Cafe to go home and weed, now that the rain has cleared).
I could place a plastic bag over the smartweed before pulling it; that would greatly reduce the possible spreading of some of the 3000 seeds or more that the plant produces. But I could also harvest it for medicinal purposes, to treat a variety of illnesses from common colds to cholera.
I doubt that I will take either of these measures. As I do every year, I'll just pull the smartweed out by the roots and admire its pretty pink flowers as I chuck them in with the other yard waste.