[2][3][4] Polypogon species vary in appearance; some are erect, while others drape over the ground in waves.

[5] Some of those are considered invasive species and noxious weeds, most notably Polypogon monspeliensis, the annual beard grass.

Numerous species now regarded as better suited to other genera: Agrostis, Alopecurus, Brachypodium, Chaetium, Gymnopogon, Muhlenbergia, Pentameris, Reynaudia, and Triniochloa.

Polypogon monspeliensis[13] was investigated for its mercury-accumulating properties as a phytoremediation plant.

This mercury hyperaccumulator sequesters the toxin in its roots in an insoluble form, reducing exposure to ecological receptors in situ and in erosion sediments.