Which weed is a sign of wet soil conditions?

Nutsedge is recognized as a sign of wet soil conditions because it thrives in areas with poor drainage and consistently moist environments. This perennial weed grows well in saturated soils, often indicating that the area does not drain properly. Its distinctive triangular stems and rapid growth compared to desired grasses make it easy to identify in landscapes.

In contrast, plantain is a common broadleaf weed found in various soil conditions, but it does not specifically indicate wetness. Aphids are pests that affect plants, rather than a sign of soil conditions. Thatch refers to a layer of organic material that develops on the soil surface but is not indicative of wet soil by itself. Thus, nutsedge is the clear choice when considering weeds associated with wet soil environments.