keys to the vascular plants of east texas - Botanical Research ...

712 JUNCACEAE/JUNCUS
Juncus interior Wiegand, (inland), INLAND RUSH. Tufted perennial 15–80 cm tall, without obvious
rhizomes; perianth 3–4.5 mm long; capsule 3–4.7 mm long. Chiefly low ground, in open
woods or prairies; widespread nearly throughout TX; sc Canada and c U.S. s to TX. Late Apr–Jul.
Juncus marginatus Rostk., (margined), GRASS-LEAF RUSH, TWO-FLOWER RUSH, NEEDLE-POINT
RUSH. Perennial 15–90(–130) cm tall, with swollen stem bases, usually inconspicuously shortrhizomatous,
sometimes tufted; inflorescence compact, of many small clusters of 2–12 flowers
each; to avoid keying errors, this species, which has thin flat leaves that are neither equitant nor
nodulose and which does not have the flowers subtended by bracteoles, can be reached either
way in the key beginning at dichotomy 6; perianth 1.8–3.3(–3.5) mm long; capsule 1.8–2.9 mm
long. Sandy old fields, roadsides, and moist areas; widespread in e 1/2 of TX, also Trans-Pecos; se
Canada and e U.S. w to SD and TX, also CA, CO, and OR. May–Jul, occasionally to Aug. [J. setosus
(Coville) Small] While var. setosus is sometimes recognized (e.g., Jones et al. 1997), we are following
Correll and Johnston (1970), Churchill (1986a), and Brooks and Clemants (2000) in not recognizing
infraspecific taxa in this species. According to Brooks and Clemants (2000), the characters
used to separate infraspecific taxa vary independently.
Juncus nodatus Coville, (with nodes, knots, or swellings), JOINTED RUSH, GRASS-LEAF RUSH. Perennial
with stems 40–120 cm tall, forming loose clumps from knotty base, without obvious
rhizomes; inflorescence rather dense; similar to J. marginatus but with nodose leaves and more
elongate inflorescences; perianth 1.2–2.2 mm long; capsule 1.9–2.5(–2.8) mm long. Damp sandy
ground or shallow water; widespread in East TX; also n Gulf Prairies and Marshes, Wichita Co.
in Red River drainage (Mahler 1988), and Mason Co. (Turner et al. 2003) in the e Edwards Plateau;
IN s to FL w to KS and TX. Jun–Jul, rarely to Nov. The specific epithet is from the ring-like
bands that are often conspicuously visible externally on the leaves where there are internal
cross-partitions.
Juncus polycephalus Michx., (many-headed), FLAT-LEAF RUSH, MANY-HEAD RUSH. Tufted perennial
from subrhizomatous base; similar to J. validus, but with smaller heads; plant 50–100 cm
tall; stems mostly crushed flat in herbarium specimens; perianth 3–4 mm long; capsule 4–5
mm long. Wet areas, usually mucky or peaty substrates; scattered in Pineywoods and s Post Oak
Savannah; also n Gulf Prairies and Marshes and e Edwards Plateau; se U.S. from MD s to FL w to
TX. Summer.
Juncus repens Michx., (creeping), CREEPING RUSH, LESSER CREEPING RUSH. Perennial with vegetative
stems arching, often creeping and rooting at the nodes, sometimes floating or growing submersed
along bottom, often forming extensive mats in shallow water; flowering stems 30 cm or
less tall; to avoid keying errors, this species, which has thin flat leaves that are neither equitant
nor nodulose and which does not have the flowers subtended by bracteoles, can be reached either
way in the key beginning at dichotomy 6; perianth 5–7(–9) mm long; capsule 3.5–5.5 mm
long. Lake and pond margins, ditches; Pineywoods and Post Oak Savannah; also n Gulf Prairies
and Marshes; se U.S. from MD s to FL w to OK and TX. Summer–fall.
Juncus roemerianus Scheele, (for Ferdinand Roemer, 1818–1891, geologist, paleontologist, and explorer
of TX), ROEMER’S RUSH. Perennial 50–150(–230) cm tall; rhizomes long and scaly; inflorescence
appearing lateral; flowers perfect or pistillate (Eleuterius 1975, 1978); perianth 2.5–3.3 mm
long; capsule (1.7–)2–3 mm long. Usually near the coast in salt marshes or other brackish situations;
Milam and Montgomery (Turner et al. 2003) cos.; also the range map in Brooks and
Clemants (2000) shows an isolated inland occurrence (county not specified) in the se part of
East TX; mainly Gulf Prairies and Marshes; mainly coastal in se U.S. from DE s to FL w to TX. In
some parts of its range this species forms large, nearly pure stands (Snogerup 1993).
Juncus scirpoides Lam., (Scirpus-like), NEEDLE-POD RUSH, SEDGE RUSH. Rhizomatous perennial
very similar to J. brachycarpus except for capsules; perianth 2–3.2(–3.5) mm long; capsule 2.9–4