Schizostachyum hainanense

Thai name: No known records.

Chinese name: 山骨罗竹 (shān gǔ luō zhú).

Distribution: THAILAND: Records of a successful introduction with correct species identification are not available. — CHINA (South): Hainan. — VIETNAM (North); in primary tropical forests.

Culm size: Length 8–20 (30) m, diameter 2–4 (5) cm.

Descriptions:

(1) "Culms ascending, 8–30 m long, 2–3(–5) cm in diam., apically long pendulous or clambering; internodes to 75 cm or longer, smooth and glabrous near base, other portions white powdery and appressed stiffly hairy; wall 1.5–2 mm thick. Branches 40–80 cm. Culm sheaths deciduous, asymmetrical, pruinose, with appressed, stiff, brown hairs, base of outer margin usually with a conspicuous, subcircular projection below point of attachment, both sides of apex rounded and extending upward but unequal, yellow-brown; auricles absent; oral setae well developed, to 2.4 cm; ligule 1.5–2 mm, margin with fimbriae 8–12 mm; blade reflexed, more than 1/2 length of sheath proper. Leaves 5–10 per ultimate branch; sheaths 4–9 cm; auricles usually inconspicuous; oral setae numerous, pale, 6–18 mm; ligule ca. 1 mm; blade oblong-lanceolate or linear-lanceolate, 6–27 × 0.6–3.7 cm. … [flowers described]. Fruit unknown." — Flora of China, accessed 17 Nov. 2019 [#1303].

(2) "… caespitose; clumped loosely. Rhizomes short; pachymorph. Culms leaning, or scandent; pendulous at the tip; 800–2000 cm long; 20–40 mm diam.; woody. Culm-internodes terete; hollow; 35–75 cm long. Lateral branches dendroid. Culm-sheaths 12–22 cm long; without auricles; setose on shoulders; shoulders with 10–15 mm long hairs. Culm-sheath ligule 9–10 mm high; fimbriate. Culm-sheath blade linear, or lanceolate; pubescent. Ligule an eciliate membrane. Leaf-blade base with a brief petiole-like connection to sheath. Leaf-blades lanceolate. Leaf-blade surface scaberulous; rough on both sides. Leaf-blade apex attenuate. … [flowers and seeds described]." — Kew GrassBase [#1335].

Images: Line drawing in Flora of China 1, 2 [#1303]. Photos in T. P. Yi & al., Iconographia Bambusoidearum Sinicarum, 2008: 4 photos on p. 056 [#1178].

Uses: Culms for basketry, other weaving articles, handicrafts, and flutes; plants as garden ornamentals.

Specimen: BS-0106 [S6] (living plant), received 23 June 2013; Hainan, China, on mountains near "Wushi Shan" [possibly, correct spelling is: Wuzhi Shan, 五指山], wild, coll. by M. S., s.n., from a sunny, rocky place near the roadside in autumn (possibly 2008).

Characteristics: Habit unicaespitose. Rhizome pachymorph, short, to about 25 cm long. Culms straight, erect below, bending outward above and widely arching, not scandent(!), over 10 m long. Young shoots conical, green, culm-leaf blades apically spreading; emerge from June/July to September/October. Culm-internodes terete, (35) 50–70 cm long, easily splittable, medium green, dull, somewhat farinose, scaberulous, with very short appressed pale hairs; diameter 4–5.5 cm; walls thin from lower culm up, moderately thick on the basal culm (1.0 cm with culm diameter 4.7 cm at 40 cm above the ground); lacuna without pith. Culm-nodes with very short appressed pale hairs when young, becoming glabrous with age, not prominent; nodal line horizontal; sheath scar marginally protruding 1 mm; supranodal line glabrous, discernible as a dark-toned slight ridge when young, ca. 1 cm above the nodal line; whitish transverse band below the nodal line 1 cm high, remaining in old culms; aerial roots none. Branch-buds solitary, usually rotund and slightly pointed on the top, usually lacking on the first two to five basal nodes (up to 140 cm above the ground). Branches many, subequal, slender, relatively short, 40–80 (100) cm long, more or less horizontal, branchless on the basal and lower culm (ca 2.5–5 m above the ground); not rebranching, or rebranching into only one further order. Culm-leaves early deciduous. Culm-leaf sheaths parabolic, ca. 21 cm long, papery, green when young, changing to ocher color or yellowish straw color, light straw-colored when dry, pruinose, with very short appressed pale(!) hairs; apex rounded, but the middle part concavely depressed truncated, symmetrical(!); base of the outer margin with a tiny(!), subcircular projection below the point of attachment, or without such a projection; margins early withering, eciliate, or with a few short pale early caducous bristles. Culm-leaf auricles of very low rims, adnate to and contiguous with the basal margins of the blade, the rims erect, glabrous, dark green to blackish green (darker than the sheath color) when young, straw-colored as the sheath when dry, margin with long pale erect or somewhat waved bristles to 25 mm long. Culm-leaf ligule rather low, ca. 1 mm high, margin with short pale bristles to 12 mm long. Culm-leaf blade rigid, leathery, initially dark green, strongly reflexed, narrow-triangular; length about 1-third to 2-thirds of the sheath length; width of the junction with the sheath apex about 1-third to 1-fifth of the width of the apex; adaxially densely short pale hairy near the base; apex long-acuminate, sharp-pointed; margins eciliate, scabrous, distally incurved. Foliage-leaves ca. 8 (10) per branchlet. Foliage-leaf sheaths rounded, not keeled, green when young, straw-colored when dry, hispid or glabrous; margins eciliate. Foliage-leaf auricles of inconspicuous rims, with many erect pale bristles, about 3–18 mm long. Foliage-leaf ligule very low, margin with short pale bristles; outer ligule a low glabrous rim. Foliage-leaf blades soft, thin, medium green, lanceolate, 15–24 × 2–3.3 cm; upper surface glabrous, slightly rough; lower surface puberulent(!); base rounded to wedge-shaped; apex attenuate; margins antrorsely scabrous; midvein proximally slightly prominent and light green; pseudopetiole relatively long, 3–6 mm.