Phalaris arundinacea
Phalaris brachystachys
alpiste roseau, phalaris roseau, reed Canary grass, roseau
short-spike Canary grass
40-230 cm.
80-100 cm.
5-40 cm long, 1-4 cm wide, elongate, often dense, always evidently branched, at least near the base;
branches to 5 cm, normally appressed but spreading during anthesis, spikelets borne singly, not clustered.
1.5-5 cm long, 0.8-1.8 cm wide, usually ovoid to ellipsoid, occasionally cylindrical, continuous, not lobed, narrowly truncate at the base, rounded at the top;
branches not evident, spikelets borne singly, not clustered.
homogamous, with 3 florets, terminal floret bisexual;
disarticulation above the glumes, beneath the sterile florets.
homogamous, with 3 florets, terminal floret bisexual;
disarticulation above the glumes, beneath the sterile florets.
subequal, 4-8.1 mm long, 0.8-1 mm wide, keels smoothly curved, usually scabrous, not or narrowly winged distally, wings to 0.2 mm wide, lateral veins conspicuous, apices acute;
sterile florets 2, subequal to equal, 1.5-2 mm, less than 1/2 as long as the bisexual florets, hairy;
bisexual florets 2.5-4.2 mm, apices acute to somewhat acuminate;
lemmas glabrate proximally, hairy distally and on the margins, dull yellow when immature, shiny gray-brown to brown at maturity, apices acute;
anthers 2.5-3 mm.
6-8.5 mm long, 1.4-2.5 mm wide, glabrous or hairy, keels winged on the distal 2/3, wings to 1 mm wide, entire, abruptly pointed;
sterile florets 2, subequal to equal, 0.6-1.2 mm, about 1/5 the length of the bisexual florets, with a tuft of hair at the base, otherwise glabrous;
bisexual florets 4.4-5 mm long, 1.3-2 mm wide, hairy, shiny, brown to dark brown at maturity, acute;
anthers 3-4 mm.
4-10 (11) mm, truncate, lacerate;
blades usually 10-30 cm long, 5-20 mm wide, flag leaf blades 4-15 cm, surfaces scabrous, margins serrate.
4-6(7) mm, rounded, lacerate;
blades 4-25 cm long, 3-8(10) mm wide.
= 27, 28, 29, 30, 31, 35.
= 12.
Phalaris arundinacea
Phalaris brachystachys
Phalaris arundinacea is a circumboreal species, native to north-temperate regions; it occurs, as an introduction, in the Southern Hemisphere. It grows in wet areas such as the edges of lakes, ponds, ditches, and creeks, often forming dense stands; in some areas it is a problematic weed. North American populations may be a mix of native strains, European strains, and agronomic cultivars (Merigliano and Lesica 1998).
The interpretation adopted here is that of Baldini (1995), who treated Phalaris arundinacea sensu stricto as the most widespread species in a complex of three species. The other two species are P. rotgesii (Husn.) Baldini, a diploid that is restricted to France and Italy, and P. caesia Nees, a hexaploid that grows in southern Europe, western Asia, and eastern to southern Africa. Phalaris rotgesii has glumes 2-3.8 mm long, sterile florets 1-1.5 mm long, bisexual florets 2-3 mm long, and anthers about 2 mm long. The corresponding measurements for P. caesia are 6-7 mm, about 2.5 mm, 4-5 mm, and 3.5-4 mm, respectively. Other taxonomists have included P. rotgesii and P. caesia in P. arundinacea. Only P. arundinacea sensu stricto has been found in North America.
A sterile form of Phalaris arundinacea with striped leaves—P. arundinacea var. picta L., also referred to as P. arundinacea forma variegata (Parn.) Druce—is known as 'Ribbon Grass' or 'Gardener's Gaiters', and is sometimes grown as an ornamental. Baldini (1995) noted that it sometimes appears to escape, and is never found far from a cultivated stand.
Phalaris arundinacea hybridizes with other species of Phalaris. One hybrid, P. xmonspeliensis Daveau [= P. arundinacea x P. aquatica] is grown for forage.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Phalaris brachystachys is native to the Mediterranean region and the Canary Islands, where it grows on waste ground, at the edges of cultivated fields, and on roadsides. It is adventive in northern Europe, Australia, and North America. It is known from a few locations in the Flora region, most of them in California.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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OR, 
WA - Local Web sites: CalFlora, CalPhotos,
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