Agrostis viridis Gouan


=Agrostis semiverticillata


=Polypogon semiverticillatus    


Poaceae (Grass Family)




Water Bent-Grass  

                                September Photo


Plant Characteristics: Perennial with long creeping and rooting stolons; culms decumbent at the base; short horizontal leaf blades, somewhat scabrous, 2-10 cm. long, ligules truncate, dentate and sometimes scaberulous, 2-6 mm. long; panicle contracted, lobed, verticillate, light green or purplish, 3-15 cm. long, the branches ascending; spikelets usually falling entire; glumes scabrous on back and keel; lemma 1 mm. long and awnless, palea nearly as long; the grain is amber colored, pointed toward the apex, rounded at the base and with a distinct groove along one side.


Habitat:  Moist ground, along irrigation ditches and near the coast, Mendocino Co. S. to S. Calif., Santa Catalina Id.; May-June


Name:  Greek, polus, many, and pogon, beard , because of the bristly infl. (Munz, Flora So. Calif. 995). Agrostis is Greek for a kind of grass.  (Jaeger 11).  New Latin, verticillatus, whorled.  (Jaeger 280).  Latin, viridis, green.  (Jaeger 281).


General:  Common in the study area.  Photographed at North Star Beach and along Back Bay Dr. at the north end of Eastbluff.  (my comments).      Agrostis is traditionally defined as including plants with awnless glumes and spikelets, which disarticulate above the glumes.  In Agrostis semiverticillata, however, the articulation is below the glumes, and the spikelets therefore fall entire.  (Mason 131).     It appears that for the reasons described by Mason, Munz reclassified this species from A. semiverticillata to Polypogon semiverticillatus as it is in the genus Polypogon that the spikelets fall entire.  A. semiverticillata is no longer listed in the Agrostis key of A Flora of Southern California, however, it is listed after A. scabra on P. 943 as an unnumbered species.   (my comments).       The 1993 Jepson Manual lists the new name, A. viridis. (Hickman, Ed. 1230).      Agrostis species have been known to cause hay fever and asthma.  (Fuller 383).     About 10 species of temperate regions.  (Munz, Flora So. Calif. 995). 


Text Ref:  Robbins et al. 52;Hickman, Ed. 1230; Mason 131; Munz, Calif Flora 1520;  Munz, Flora So. Calif. 996; Robbins et al. 52; Roberts 45.

Photo Ref:  May 5 83 #23; May 3 84 #16.

Identity: by R. De Ruff, confirmed by F. Roberts.

Computer Ref:  Plant Data 37.

Have plant specimen.

Last edit 4/8/03.


                                    May Photo