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

SCLERIA/CYPERACEAE
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5. Lowest lateral spikelet cluster erect, sessile or on a stiff, � erect stalk to 20(–90) mm
long; achene body glabrous; uppermost lateral spikelet cluster with bract (including
sheath) usually 3/4 or more the length of terminal internode; species rare in East TX,
known only from Newton Co. _______________________________________________ S. reticularis
2. Achene body not subtented by a basal pad, the base of the achene body � triangular.
6. Inflorescence with a single terminal cluster of spikelets; scales of spikelets and leaf sheaths
glabrous.
7. Achene body ca. 2(–3) mm long, at very base triangular with a pair of iridescent pits on
each of the three sides _____________________________________________________ S. georgiana
7. Achene body ca. 3–4 mm long, at very base triangular, but without pits ______________ S. baldwinii
6. Inflorescence spike-like and interrupted, with 3–8 distinct, well-spaced clusters of spikelets
in addition to the terminal cluster; scales of spikelets and sometimes also leaf sheaths
with conspicuous � straight hairs ________________________________________________ S. distans
1. Achene body either conspicuously rough (reticulate or warty) OR with horizontal ridges.
8. Inflorescence solitary, terminal, spike-like, and interrupted, with (2–)3–7(–9) distinct, well-spaced
clusters of spikelets in addition to the terminal cluster; plants annual, without rhizomes; achenes
without basal pad, the achene body usually 1–1.5 mm long ___________________________ S. verticillata
8. Inflorescence EITHER a single head-like cluster of spikelets with 1 or 2 additional clusters
sometimes in close proximity to the first OR inflorescence with both terminal and axillary
compact clusters; plants annual or perennial, with or without rhizomes; achenes with a disklike,
ring-like, or 3-lobed (and almost calyx-like) basal pad, the achene body 1–3.6 mm long.
9. Basal pad not distinctly 3-lobed, but with 3–6 tubercles; inflorescence a single head-like
cluster of spikelets with 1 or 2 additional clusters sometimes in close proximity to the first,
but without obvious branches.
10. Achene body (1.5–)2–3.6 mm long; basal pad bearing 3 entire or 2-lobed tubercles (since
the lobing is often irregular and sometimes deep, what appear to be 4–6 tubercles
can sometimes be observed) __________________________________________________ S. ciliata
10. Achene body 1–2(–2.5) mm long; basal pad bearing 6 tubercles (these in pairs) ______ S. pauciflora
9. Basal pad 3-lobed, almost calyx-like in appearance, without tubercles; inflorescence with
both terminal and axillary compact clusters, usually with visible branches.
11. Lowest lateral spikelet cluster spreading or drooping on filiform, flexuous stalk (15–)
20–100 mm long; achene body usually with tufts or lines of spreading, whitish or tawny
hairs on ridges, rarely glabrous; uppermost lateral spikelet cluster with bract (including
sheath) usually 1/4–3/4 the length of terminal internode; species widespread in e part
of East TX __________________________________________________________ S. muehlenbergii
11. Lowest lateral spikelet cluster erect, sessile or on a stiff, � erect stalk to 20(–90) mm
long; achene body glabrous; uppermost lateral spikelet cluster with bract (including
sheath) usually 3/4 or more the length of terminal internode; species rare in East TX,
known only from Newton Co. ______________________________________________ S. reticularis
Scleria baldwinii (Torr.) Steud., (probably for William Baldwin, 1779–1819, botanist and physician
of Pennsylvania), BALDWIN’S NUT-RUSH. Perennial 30–90 cm tall, similar to S. georgiana but
with rhizomes relatively thicker, more spreading, and knotty; inflorescence a single head-like
cluster; achene body usually not subtended by a basal pad, 3–4 mm long, smooth or longitudinally
ribbed, triangular at very base, but without pits. Wet pinelands and savannahs, margins
of swamps, and wet areas, often in shallow water, sandy or sandy peat soils; known in TX from
Harris, Newton (BRIT), and Tyler (Turner et al. 2003) cos.; se U.S. from SC s to FL w to TX. May–
Oct. [S. costata (Britton) Small] According to Kessler (1987), this species is often confused with S.
triglomerata. However, it can be distinguished by the larger size of the achenes (3–4 mm versus
1.5–3 mm in S. triglomerata) and the lack of the basal pad covered with a rough white crust,
characteristic of S. triglomerata. While not officially designated as such (e.g., TOES 1993; Carr