Carpetweed is a late-starting, rapidly growing summer annual. Which growth habit describes carpetweed on the soil surface?

• A. A dense upright clump
• B. A flat circular mat
• C. A creeping stolon network
• D. A rosette

Answer: (B)

Carpetweed grows very close to the ground and spreads across the soil surface, forming a low, prostrate, mat-like patch. This spreading habit means it blankets the soil in a flat, circular patch rather than rising upright, forming runners, or staying as a tight center rosette. The rapid, horizontal expansion typical of a late-starting summer annual is what creates that flat circular mat appearance. The other growth forms describe plants that stand upright, send out creeping runners, or cluster in a basal rosette, which don’t match carpetweed’s surface-spreading behavior. So the soil-surface description that best fits carpetweed is a flat circular mat.