Panicum rigidulum subsp. abscissum

(Swallen) Freckmann & Lelong
Treatment appears in FNA Volume 25. Treatment on page 477.

Plants yellowish-green. Culms compressed, densely cespitose. Sheaths strongly keeled, 3-6 mm wide from the keel to the margins, truncate or broadly auriculate, occasionally ciliate distally; ligules minute, membranous; blades 0.7-1.5 mm wide from the blunt keel to the margins, to 2.5 mm wide overall, thick, curved or flexuous, rigid, glabrous or scabridulous on both surfaces and along the margins, bases much narrower than the subtending sheaths, margins often sparsely ciliate, with long, slender hairs near the base. Panicles slender, purplish, long-exserted; branches few, appressed or ascending, with relatively few spikelets. Spikelets 2.4-2.8 (3) mm, purplish, glabrous, obliquely set on the pedicels, mostly abortive. Lower glumes 1.6-2 mm, often divergent; upper glumes and lower lemmas subequal, often spreading apart.

Discussion

Panicum rigidulum subsp. abscissum is endemic to central Florida. It usually grows in marshy, sandy ground, but is occasionally found in dry, sandy sites (e.g., the type specimen, collected near Lake Sebring).

Panicum rigidulum subsp. abscissum is very similar vegetatively and reproductively to subsp. pubescens and subsp. combsii. In addition, its spikelets also suggest those of P. virgatum.

Selected References

None.

Lower Taxa

None.

No values specified."decumbent" is not a number."thickish" is not a number."varying" is not a number.

puberulent +
acute +, obtuse +, rounded +  and attenuate +
anatomy +  and kranz +
Robert W. Freckmann +  and Michel G. Lelong +
(Swallen) Freckmann & Lelong +
1 (?) +  and 3 (?) +
keeled +  and rounded +
divergent +  and parallel +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
membranous +
much narrower +
disarticulating +  and pseudopetiolate +
non-radiate +  and radiate +
flexuous +  and curved +
8 cm80 mm <br />0.08 m <br /> (50 cm500 mm <br />0.5 m <br />) +
scabridulous +
folded +  and flat +
ascending;appressed +
spikelike +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
not developed +
terete +  and compressed +
sometimes longer +
fimbriate +
small green +
branched +  and simple +
ascending +  and erect +
compressed +
35 cm350 mm <br />0.35 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
woody +  and hard +
Conn. +, N.J. +, N.Y. +, W.Va. +, Del. +, D.C. +, Wis. +, B.C. +, N.S. +, Ont. +, Mass. +, Maine +, N.H. +, R.I. +, Vt. +, Fla. +, Ala. +, Kans. +, Ky. +, La. +, Mo. +, Okla. +, Pa. +, Tenn. +, Tex. +, Va. +, Puerto Rico +, N.C. +, S.C. +, Md. +, Calif. +, Miss. +, Ark. +, Ill. +, Ga. +, Ind. +, Mich. +, Ohio +  and Oreg. +
capillary +
germination +
pistillate +  and staminate +
sometimes longer +
compressed +  and terete +
subtending +
pubescent +  and glabrous +
tuberculate +
unequal +
membranous +
well-developed +
uncinate +
minute +
Oval (?) +  and Round (?) +
bracteate +  and ebracteate +
hollow +  and solid +
coriaceous +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
membranous +
inconspicuous +
2/5 +  and 3/4 +
acuminate +, acute +  and truncate +
0.16 cm1.6 mm <br />0.0016 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0mm;2.5mm +
complex +  and simple +
scabridulous +
concealed +  and prominent +
2 +  and 1 +
subterranean +
long-exserted +
1/3 +  and 3/4 +
9 cm90 mm <br />0.09 m <br /> (40 cm400 mm <br />0.4 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
dry +  and fleshy +
auriculate +, truncate +  and keeled +
3mm +  and 6mm +
pubescent +  and glabrous +
in triplets +  and paired +
unisexual +  and bisexual +
lanceolate +
0.24 cm2.4 mm <br />0.0024 m <br /> (0.28 cm2.8 mm <br />0.0028 m <br />) +
1 +  and 3 +
compound +  and simple +
fused +  and free +
2 +  and 3 +
dome--shaped +  and triangular +
scabridulous +
Gramineae +
Panicum rigidulum subsp. abscissum +
Panicum rigidulum +
subspecies +
membranous +
0.14 cm1.4 mm <br />0.0014 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
2/5 +  and 3/4 +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
pubescent +  and glabrous +
rugose +  and verrucose +
chartaceous-indurate +  and rigid +
aquatic +  and terrestrial +
dioecious +, monoecious +  and synoecious +