Podagrostis

(Griseb.) Scribn. & Merr.
Treatment appears in FNA Volume 24. Treatment on page 693.
 TaxonIllustrator 
FNA24 P267A Podagrostis pg 695.jpegPodagrostis aequivalvis
Podagrostis humilis
Sandy Long
Sandy Long

Plants perennial; cespitose, sometimes rhizomatous. Culms 5-90 cm, erect or decumbent at the base. Leaves basally concentrated; sheaths open to the base, smooth, glabrous; auricles absent; ligules membranous, scabridulous dorsally, truncate to subacute, entire to lacerate; blades flat or involute. Inflorescences panicles, exserted at maturity, not disarticulating; branches ascending to erect. Spikelets pedicellate, weakly laterally compressed, with 1 floret; rachillas usually prolonged 0.1-1.9 mm beyond the base of the floret, sometimes absent, especially from the lower spikelets within a panicle, apices glabrous or with hairs, hairs to 0.3 mm; disarticulation above the glumes, beneath the floret. Glumes equal or the lower glumes longer than the upper glumes, flexible, acute to acuminate, sometimes apiculate, unawned; calluses glabrous or hairy, hairs to 0.5 mm; lemmas membranous, (3) 5-veined, veins mostly obscure, sometimes prominent distally, apices truncate to rounded or acute, unawned or awned, awns to about 1.3 mm, usually subapical, occasionally attached near midlength; paleas more than 1/2 as long as the lemmas, 2-veined, thinner than the lemmas; anthers 3. Caryopses shorter than the lemmas, concealed at maturity, x = 7.

Discussion

Podagrostis is a genus of six or more species that grow in cool, wet areas. In the past, its species have been included in Agrostis. Four or more species are native to Central and South America, and two to the Flora region. Podagrostis differs from Agrostis in its combination of a relatively long palea and, usually, the prolongation of the rachilla beyond the base of the floret. It differs from Calamagrostis in the poorly developed callus hairs and awns.

Key

1 Glumes 2.3-4.3 mm long, generally equal; rachilla prolongations 0.5-1.9 mm long Podagrostis aequivalvis
1 Glumes 1.6-2.3 mm long, lower glumes equal to or longer than the upper glumes; rachilla prolongations 0.1-0.6 mm long Podagrostis humilis

"decumbent" is not a number.

... more about "Podagrostis"
membranous +  and scarious +
with hairs +  and glabrous +
truncate +  and rounded or acute +
M.J. Harvey +
(Griseb.) Scribn. & Merr. +
1 (?) +  and 3 (?) +
straight +
attached +
basal +  and terminal +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
not evident +
involute +  and flat +
ascending;erect +
spikelike +
hairy +  and glabrous +
not branching +
decumbent +  and erect +
5 cm50 mm <br />0.05 m <br /> (90 cm900 mm <br />0.9 m <br />) +
not woody +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
sterile +  and bisexual +
compressed +
reduced +
shorter or longer +
subtending +
unequal +
uncinate +
0 cm0 mm <br />0 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
lanceolate +  and ovate +
membranous +
truncate +  and subacute entire +
membranous +
inconspicuous +
lanceolate +
acute +  and acuminate +
concealed +  and prominent +
2 +  and 1 +
hairy +  and glabrous +
well-developed +
/2 +  and 1 +
2-keeled +
thinner +
spikelike +
dry +  and fleshy +
bjorkman1960a +  and carlbom1967a +
1 +  and 60 +
compressed +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (5 cm50 mm <br />0.05 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Gramineae +
Podagrostis +
Poaceae tribe Poeae +
membranous +
parallel +  and converging +
prominent +  and obscure +
plant +  and cespitose +
aquatic +  and terrestrial +