It’s Wednesday (believe it or not), which means it’s time to celebrate Wednesday’s weed! Weed of the week is a species that’s much more important than its diminutive size would indicate: Arabidopsis thaliana. This species (thale cress) is the most common plant model organism, used in similar ways to Drosophila fruit flies, mice, and E. coli in lab experiments. It has been used in a number of genetic, physiological, and developmental studies (to name only a few categories of work in which it has been important), and has helped us greatly improve our knowledge of the way that plants work.
Of course, it’s also a weed. A. thaliana is native to Eurasia and Africa, but doesn’t belong in North America. It’s small, but can be a somewhat unsightly lawn pest. This particular one was photographed (on the hood of a car - spot the botanist in the reflection!) near where it was pulled in a Virginian parking lot.