Nutsedges are characterized by what type of stem structure?

Nutsedges are characterized by solid, triangular stems with leaves extending in three directions, which is the reason this option is correct. This unique stem structure is a distinguishing feature of sedges, setting them apart from grasses and other turf weeds. The triangular shape of the stem is notable and helps in identifying nutsedges in the field.

The leaves of nutsedge originate from three distinct sides of the stem, which can be visualized as forming a triangle. This structural characteristic is essential for proper identification and management of nutsedge in ornamental and turf settings.

Other options describe stem structures that do not accurately depict the nutsedge. For example, hollow and rounded stems are more typical of certain grass species, while smooth rounded stems with few leaves and thick stems with alternating leaf patterns do not reflect the typical morphology of nutsedges. Understanding these structural characteristics is essential for pest management and effective control strategies.