Paspalum thrasyoides, commonly known as Knot grass or Knotroot paspalum, is a perennial grass native to tropical and subtropical regions of the Americas, including savannas, open woodlands, and disturbed areas such as roadsides and pastures. It typically reaches a height of 1.5-3 feet (0.46-0.9 meters) and is characterized by its sprawling habit and knotty rootstocks. The grass has narrow leaves and produces yellow or green flowers that are generally inconspicuous, blooming in the summer. The inflorescence is a raceme, which can be a distinguishing feature.

Knot grass is appreciated for its rapid growth and adaptability to various soil types, making it useful for erosion control and as a turfgrass in warmer climates. It is also used for forage in pastures. However, its aggressive growth can make it a weed in some settings. In cultivation, it requires full sun to part shade and can tolerate a range of soil conditions, from clay to sandy loam, provided they have medium to fast drainage. Gardeners should be cautious as Paspalum thrasyoides can spread outside its native range, particularly in similar warm climates.CC BY-SA 4.0