Which weed is known as oxalis or sour grass?

• A. Prostate knotweed
• B. Wood sorrel
• C. Broadleaf plantain
• D. Quack grass

Answer: (B)

Knowing common weed names helps you identify what you’re dealing with. Oxalis, or sour grass, is wood sorrel. It’s easy to spot in turf by its trifoliate leaves that are shaped like tiny hearts and grow close to the ground, often with small yellow flowers. The leaves have a sour taste when crushed because of oxalic acid, which is why people call it sour grass. The other plants listed are different types—prostrate knotweed is a low-growing weed with small leaves, broadleaf plantain has a larger oval leaf, and quack grass is a creeping grass. Since the name oxalis matches wood sorrel, that is the correct identification.