Gigantochloa wrayi

Gigantochloa wrayi Gamble
  • Synonyms: Gigantochloa maxima var. viridis Holttum.
  • Thai name: ไผ่คายดำ (phai khai dam) (Krabi). Malay names: Buloh beti; buloh mata rusa; muloh minyak.
  • Distribution: Peninsular THAILAND: Chumphon, Krabi, Nakhon Si Thammarat, Trang; in lowland forest at 50–100 m altitude. MALAYSIA (North), in lowlands, also cultivated in villages. MYANMAR.
  • Descriptions:
    (1) "Culms medium sized, up to 7 cm. thick, not hairy; culm-sheaths up to 27 cm., dark-hairy when young, blade reflexed, green when young, narrow and narrowed to the base, dark-hairy on the upper surface; auricles firm, low, entire, with a few bristles near the outer ends; ligule lacerated with the lacerations prolonged into bristles, up to 1 cm. high; leaf-blades up to 40 x 6 cm., lower surface fine-hairy; stalk 8 mm. long; auricles small, often bristly; ligule short. ..." — H. B. Gilliland, Revised Flora of Malaya, vol. 3, 1971: p. 33 [#1039].
    (2) "Culm sheaths green, occasionally streaked with paler green, covered with dark brown hairs; blade broadly lanceolate, spreading to reflexed; auricles low rims 0.5–1.5 mm high, glabrous to frequently with scattered fine bristles near the ends; ligule 6–11 mm long, deeply divided to form bristle-like lacerations 3–7 mm long. Culms to 6–12(–15) m tall, commonly 2–8(–12) cm diameter; internodes 25–40 cm long, dark green, occasionally streaked with paler yellowish green at the basal part of the culm, without white wax, with scattered dark hairs near the top of the internode. Leaf: blades 9–40 cm long, 1.2–6 cm wide, pale short-hairy below; stalk 2.5–4 mm long; auricles small lobes hardly 0.5 mm high, glabrous to fine-bristly; ligule a subentrie rim 0.5–1.5 mm long, not bristly ... [flowers described]." — K. M. Wong, Bamboos of Peninsular Malaysia, 1995: p. 142-143, fig. 80 [#1210].
    (3) "Densely tufted, sympodial bamboo. Culm erect, slightly arching outwards, up to 12 m tall, diameter 2–20 cm, plain green or sometimes streaked yellow at the base; internodes non-waxy, up to 40 cm long, with scattered appessed dark-brown hairs on the upper parts; nodes not conspicuously swollen. Branches at each midculm node arising from a single bud, consisting of a dominant primary branch, 1–2 subdominant branches from its base and several lesser branchlets of higher orders. Culm sheath pale green, sometimes with faint yellow stripes, covered with dark brown hairs; blade broadly triangular on lower sheaths, broadly lanceolate on midculm and upper sheaths, green or sometimes flushed purple, spreading to reflexed, hirsute at base and along midrib on lower half; ligule lacerate, the base 1–2 mm tall, the lacerations to 8 mm long, bristly along rim when young; auricles low and rimlike, 2–4 mm long, sometimes raised at the outer ends, glabrous except for a few scattered pale bristles 2–5 mm long near the outer ends, dark green to dark purple. Leaf blade 9–40 cm × 1.5–6 cm, lower surface covered with soft pale hairs; ligule subentire, not bristly, 1–2 mm long; auricles small rounded lobes 1–2 mm long. Pseudospikelet 10–20 mm long, with 2–3 gemmiferous bracts, 3–4 glumes, 3–4 perfect florets and a vestigial terminal floret respresented by an empty lemma 8–17 mm long. Caryopsis cylindrical-ellipsoidal, about 10 mm long, grooved on one side, apex thickened and hairy." — K. M. Wong in S. Dransfield & E. A. Widjaja (editors), Plant Resources of South-East Asia No. 7, Bamboos, 1995: p. 124-126, fig. [#1226].
    (4) E. A. Widjaja, A Revision of Malesian Gigantochloa (Poaceae–Bambusoideae), in Reinwardtia, vol. 10(3), 1987: p. 339-341, fig. 18-19 [#1224].
    (5) "Culms densely tufted, straight and erect, up to 12 m tall, 4—10 cm in diameter; internodes to 50 cm long, green, glaucous, scattered with dark-brown hair when young; nodes not swollen; walls relatively thin, about 0.6—0.8 cm thick at mid-culm portion. Branches developing only on the upper part of the culms; mid-culm branch complements with several branches at each node, the primary one dominant, 1—2 subdominant branches from its base and often several lesser branches. Culm leaves deciduous, coriaceous-crustaceous, yellow-green, 21—27 cm long by 16—25 cm wide, top slightly convex or truncate to slightly concave, back covered with appressed dark-brown hairs; blades lanceolate, reflexed, 14—16 cm long by 2.5—3 cm wide near the base, covered with dark brown hair on adaxial sides; auricles continuing from base of the culm-leaf blade, rim-like, almost reach edges of the sheath, about 1—2 mm tall by 15—20 mm long, margins fringed with bristles 5—10 mm long, readily deciduous; ligules irregularly dentate, up to 5 mm high, fringed with readily deciduous bristles to 5—10 mm high. Leaves 4—8 per branchlet; blades 7—25 cm long by 0.8—2.5 cm wide, lower surface pubescent, tessellate, bases oblique-acute to oblique-rounded, pseudo-petiole 3—8 mm long; leaf sheaths 5—9 cm long, covered with white to pale-brown hair when young then become glabrous; auricles small, ear-like or lobe-like, up to 1 mm long, glabrous, sometimes fringed with bristles 2—3 mm long at the end of the lobe; scale-like callus inconspicuous to present, glabrous, 1 mm by 2 mm, margin sub-entire or covered with minuscule spines; ligule low rim 1 mm high, margin irregularly dentate, sometimes fringed with bristles up to 2 mm long; secondary veins 7—9 pairs, intermediate veins 5—7. … [flowers described, seeds unknown]". — C. Rattamanee, Taxonomic Revision of Gigantochloa (Poaceae: Bambusoideae) in Thailand …, Thesis, Kasetsart Univ., 2014: p. 124-129, fig. 48-50 [#1225].
    (6) J. S. Gamble, Bambuseae Brit. India, 1896, p. 64 [#1230].
    (7) Kew GrassBase.
  • Images: Line drawing in J. S. Gamble, Bambuseae Brit. India, 1896, pl. 55 [#1230].
  • Uses: Culms for baskets and cages, incense sticks, handicrafts, fences, house walls, household tools.
  • Comments: Closely related to G. scortechinii, which has farinose internodes, whereas G. wrayi is not farinose.

Gigantochloa wrayi 'Impian'
  • Thai names: Not recorded.
  • Distribution: MALAYSIA, in cultivation.
  • Specimens: BS-0303 [†] (living plants), received from Rimba Ilmu Botanical Garden, Malaysia, as "Gigantochloa wrayi", by C. S. in Sep. 2009, died mid-2017 after flowering.
  • Characters: Culm internodes striped in whitish green and cream.
  • Uses: Plants as garden ornamentals.
  • Flowering and seeding: The plant, a single clump, started gregarious flowering in January/February 2017. Seed-containing spikelets were found in late March 2017. In more than 10% of spikelets, perhaps even more than 20%, a seed has developed. Spikelets drop off early. Little over 100 seed-containing spikelets were harvested 29–30 March, of which 100 were sown on 31 March 2017. Record on seed germination in Compilation of Bamboo Seeds: BS-0303A [C9,Z]. Three strong seedlings were selected, BS-0303B, BS-0303C, and BS-0303D, for further observation and cultivation.
  • Comments: The characters of culm-leaves of BS-0303 do not match closely with those as described by K. M. Wong. Further investigation is needed to proof the identity.


Gigantochloa wrayi 'Impian' (BS-0303):
Young shoot with culm-leaf, showing a patent culm-leaf blade, and a tall brownish lacerated ligule which extends into whitish bristly fringes (left);
internode on lower culm (center); habit of the plant, which is in an early stage of flowering, 1st March 2017 (right)


Gigantochloa wrayi 'Impian' (BS-0303): Flowering branch (left); spikelets containing seed (BS-0303A, center); seedlings, 23rd day after sowing (BS-0303A, right)