Dendrocalamus sinicus

Synonyms: Sinocalamus sinicus (L. C. Chia & J. L. Sun) W. T. Lin, Bamboo Res. No. 42, 1990: 6; Dendrocalamus sinicus f. aequotus K. L. Wang (place of publication unknown).

Thai names: ไผ่จีน (phai chin) (BKF [#1368]); ไผ่มังกร (phai mang gon); ไผ่มังกรยักษ์ (phai mang gon yak); ไผ่เป๊าะ (phai po).

Chinese name: 巨龙竹 (jù lóng zhú), can be translated as "giant dragon bamboo".

Lao names: Bo', puak.

English name: Giant Dragon Bamboo.

Distribution: THAILAND (North): Provinces of Mae Hong Son and Chiang Mai: presumably introduced and planted in early times, presumably not naturally occurring. Mae Hong Son Province: Mae Pai (คลองแม่ป่าย), (local name: ไผ่เป๊าะ phai po, "pai poh"), for Kew specimens K000631976 and K000631977 [#1333]; it could not be clarified whether the two specimens actually represent D. sinicus or the confusingly similar D. copelandii. Chiang Mai Province: Samoeng District, a stand, named ไผ่หกวัดจันทร์ (phai hok wat chan), flowered in 2018, identified as D. sinicus and believed to have been planted a long time ago.. — CHINA (South): south-western and southern Yunnan, native, wild and planted, 600–1,000 m altitude; Guangxi. — LAOS (L. Inthakoun and C. O. Delang, Lao Flora, 2008 [#1140]).

Culm size: Height 20–30 m (140 ft = 42.7 m), dia­meter 20–30 (32) cm. Another record: Culm length 46 m, diameter 36 cm (Xinhua News Agency Aug. 29, 2003). "The Xinhua News Agency carried this interesting article about the largest bamboo in the world … in August 29, 2003. The bamboo, identified as Dendrocalamus sinicus, was found in a plantation in the Menghai County of Xishuangbanna, Southwestern China. The specimen shown in the photo has a diameter of 25 cm (10 in) but according to the report some culms in the plantation reach a diameter of 36 cm (14 + inches = waistline of 35 inches) and are up to 46 m tall. (Source: Bamboo Phil, January – March 2009)" (Ua Yarwng vol. 1, 2010).

Descriptions:

(1) "18. Dendrocalamus sinicus L. C. Chia & J. L. Sun, Bamboo Res. 1(1): 10. 1982. 歪脚龙竹 wai jiao long zhu. Culms 20–30 m, 20–30 cm in diam.; internodes 17–22 cm. Culm sheaths deciduous or persistent, initially yellow-green, thickly leathery; auricles absent; ligule ca. 6 mm; blade erect. Leaf sheaths initially slightly hairy, becoming glabrous; ligule 1.5–2 mm; blade 20–40 × 4–6.5 cm. Pseudospikelets 1 or more. Spikelets 30–35 × 6.5–7.5 mm; florets 5 or 6. Glumes 1.2–1.5 cm, abaxially slightly hairy, apex mucronate; lemma 17–25 mm; palea 5-veined between keels, apex bifid. Filaments 1.5–3 cm; anthers 8–12 mm. Style long; stigma 1. Fruit unknown. * 600–1000 m. Yunnan." — Flora of China, accessed 27 Oct. 2020 [#1303].

(2) "Habit: Perennial; caespitose. Rhizomes short; pachymorph. Culms erect; nodding at the tip; 2000–3000 cm long; 200–300 mm diam.; woody; with aerial roots from the nodes. Culm-internodes terete; with small lumen; 17–22 cm long; distally mealy. Lateral branches dendroid; arising from upper culm. Branch complement many; with subequal branches. Culm-sheaths persistent; coriaceous; hispid; hairy above; with appressed hairs; with dark brown hairs; without auricles; glabrous on shoulders. Culm-sheath ligule 6 mm high; entire, or dentate. Culm-sheath blade triangular; as wide as sheath at base; erect; pubescent; acuminate. Leaf-sheaths glabrous on surface, or puberulous. Leaf-sheath oral hairs lacking. Leaf-sheath auricles absent. Ligule an eciliate membrane; 1.5–2 mm long; erose. Leaf-blade base with a brief petiole-like connection to sheath. Leaf-blades oblong; 20–40 cm long; 40–65 mm wide. Leaf-blade venation with 20–26 secondary veins; with distinct cross veins. Leaf-blade surface glabrous, or puberulous; hairy on both sides. Leaf-blade apex acuminate. Inflorescence: Synflorescence bractiferous; clustered at the nodes; in stellate clusters; 2–4 cm between clusters; pubescent on internodes; with glumaceous subtending bracts; with axillary buds at base of spikelet; prophyllate below lateral spikelets; leafless between clusters. Fertile spikelets sessile. Fertile Spikelets: Spikelets comprising 5 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; compressed slightly; 30–35 mm long; 6.5–7.5 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes suppressed between florets. Glumes: Glumes two; persistent; similar; shorter than spikelet. Lower glume ovate; 12–15 mm long; chartaceous; without keels. Lower glume lateral veins with cross-veins. Lower glume surface puberulous. Lower glume margins ciliolate. Lower glume apex acute; mucronate. Upper glume ovate; 12–15 mm long; chartaceous; without keels. Upper glume lateral veins with cross-veins. Upper glume surface puberulous. Upper glume margins ciliolate. Upper glume apex acute; mucronate. Florets: Fertile florets increasing in size upwards. Fertile lemma ovate; 17–25 mm long; chartaceous; without keel. Lemma apex acuminate. Palea chartaceous; 2-keeled but the uppermost without keels. Palea keels ciliolate. Palea surface pubescent; hairy on back. Palea apex dentate; 2 -fid. Flower: Lodicules absent. Anthers 6; 8–12 mm long; anther tip apiculate. Filaments free, or united in a tube; 1.5–3 mm long. Stigmas 1. Ovary pubescent on apex. Fruit: Caryopsis with adherent pericarp." — Kew GrassBase, accessed 27 Oct. 2020 [#1335].

Images: Line drawing in Flora of China [#1303]. — Photos in AsianFlora (culm) [#1332]; BambooCraft.net (culm) [#1341]; Facebook (culm); Yunnan Bamboo Nursery FMXG (culms). — Photos of shoots of young plants, by Niramit Sareerudt on Facebook, 5 Dec. 2013. — Photos of culms and shoots of old plants, by Niramit Sareerudt on Facebook, 6 Dec. 2013. — Photos of Dendrocalamus sinicus introduced from Yunnan, flowering in Thailand, by Nanbamboo น่านแบมบู on Facebook, 9 Feb. 2014. — Photos of Dendrocalamus sinicus, by Thoop Nakasen on Facebook, 16 Sep. 2015. — Photos of habit, culms, and flowers of Dendrocalamus sinicus, by Thoop Nakasen on Facebook, 29 Nov. 2017. — Photos (culms, habit) in H. C. Tan, 2012: 56-57 [#1195] — Photos of culms and seeds, by Lihua Jiang on Facebook, 15 June 2022.

Characteristics: Distinguishing vegetative characteristics of three giant species of genus Dendrocalamus.
Characteristics of the species Dendrocalamus sinicus, D. copelandii and D. giganteus are compared. To distinguish D. giganteus from the other two species is relatively easy. Although the young shoots of all three species look confusingly similar, D. giganteus is easy to distinguish from the other two species when the culm-leaves have become dry. The culm-leaves of D. giganteus detach from the nodes relatively early and drop off, and their structure is hard and brittle, whereas both D. sinicus and D. copelandii have persistent culm-leaves with a paper-like structure that decays early. However, both these species, D. sinicus and D. copelandii, are so similar that reliable differentiation based on vegetative characteristics alone is extremely difficult, if not impossible.

Comments:

(1) Dendro­calamus sinicus is known as the world's tallest and biggest bamboo species with self-supporting culms (a few climbing species, hence without self-supporting culms, can reach a much longer culm length).

(2) The height of plants grown in Chiang Mai Province is not recorded; the plants from Mae Hong Son are only up to 15 m tall.

(3) The description of 平节龙竹 (píng jié lóng zhú), Dendrocalamus sinicus f. aequotus K. L. Wang, is available in Chinese only and reads: 本变型与原变型之区别在于秆基部节间正常，并不歪斜。 (cn312.cn). This name stands for the straight form of Dendrocalamus sinicus. The botanical name with the forma epithet "aequotus" is not listed in the International Plant Name Index (IPNI) [#1349] and may have been invalidly published. — (translation of the Chinese text by Che, pers. comm., email, 17 Oct. 2020).

(4) I have no reason to doubt that Yunnan seeds distributed by 蒋丽华 as "Dendrocalamus sinicus" are true Dendrocalamus sinicus. It should be considered that it has been claimed that Dendrocalamus sinicus also occurs in northern Thailand, where Dendrocalamus copelandii also occurs. The latter species seems to be very variable and similar to Dendrocalamus sinicus; Dendrocalamus copelandii flowered in Thailand at about the same period of time as Dendrocalamus sinicus in Yunnan. It would therefore be helpful to better understand the relationship between Dendrocalamus sinicus and Dendrocalamus copelandii, but I do not know of a molecular study that includes both species.

Characteristics (recorded on 30 Nov. 2020, based on BS-0617, a plant 10 years old as of March 2021, which has not yet reached its ultimate size for its location, current clump height estimated at 12 m, largest culm diameter 8.5 cm): Habit caespitose, tight clump. Rhizome pachymorph, short. Culms straight, erect, slightly bending outwards above, nodding apically. Young shoots conical, sheaths reddish with dark hairs, sheath margins dark colored, eciliate, culm-leaf blades erect on top, patent below, purplish black; emerge from April/May to August/September. Culm-internodes terete, 25–30 cm long; internodes of small diameter reddish when young, mid-green later, initially sparsely short brown hairy, almost glabrous, farinose on the entire internode or in part, internodes of large diameter dull mid-green, glabrous, without hairs, marginally rough to touch, not smooth, thinly farinose all over the internode or with farinose splotches on the internode, the farina persistent for 1 growth season or little longer, not easy to wipe off, but can be scraped off; wall thickness thin (walls 0.7 cm by 5 cm in diameter at 1.15 m above the ground). Culm-nodes glabrous, flat; nodal line horizontal; sheath scar not or marginally (0.5 mm) protruding, 0.5–1 mm high. usually with persistent remnants of the decayed sheath; supranodal line obscure, without a ridge; with aerial roots on basal nodes up to 20 cm from the ground. Branch-buds solitary, small, rotund, diameter ca. 8 mm, usually present from the basal nodes up on culms with small diameter, usually absent or obscure on nodes up to about 1–1.5 m from the ground on culms with large (7+ cm) diameter. Branches several, unequal, the central one dominant; lower culm unbranched, with branches from about the 18th node up; branching [not seen, possibly] intravaginal; rebranching. Culm-leaves persistent and decaying on the basal culm (not easily removable, remnants remain attached), late deciduous (in the second season) on unbranched nodes of the lower and mid-culm, deciduous on branched nodes of the mid-culm and upper culm. Culm-leaf sheaths parabolic, ca. 30–32 cm long on the lower culm, longer than the internode on the basal culm, longer than or almost as long as the internode on the lower culm; papery, reddish-green when young, straw-colored to reddish brown when dry, covered with mid-brown to dark-brown appressed hairs, glabrous near the apex; apex rounded, slightly concave at the attachment of the sheath blade; margins dark or reddish colored when young, usually eciliate, occasionally pale ciliate on sections when young. Culm-leaf auricles (on the lower culm with ca. 8 cm in diameter) inconspicuous very short and low glabrous somewhat pleated and aslant rims, adnate to the basal margins of the blade, the ends not reaching the sheath margin, ca. 5–7 mm wide, ca. 1–1.5 mm high near the blade base, dark colored, deep purplish when young, without oral setae. Culm-leaf ligule low, ca. 2 mm high, continuous with the apical sheath margin, purplish black when young, dark colored when dry, margin entire to subentire. Culm-leaf blades initially erect, soon becoming deflexed, thickly papery, glabrous on both surfaces, persistent or late caducous, broadly lanceolate on the lower and mid-culm, almost triangular on the basal culm, purplish black to purplish green when young, reddish brown when dry. Foliage-leaves about (6) 11–15 (17) per branchlet. Foliage-leaf sheaths glabrous, yellowish-green, reddish towards the apex when young; margins eciliate(?). Foliage-leaf auricles absent, or inconspicuous very low glabrous rims; oral setae none. Foliage-leaf ligule conspicuous, subentire or irregularly serrate, orange to orange-brown when young. Foliage-leaf blades, mid-green, lanceolate to ovate-lanceolate, large, up to 37 × 8 cm (on the immature plant), glabrous on both surfaces, slightly pubescent beneath when young; base rounded to acuminate; apex attenuate; margins antrorsely scabrous; midvein somewhat prominent; pseudopetiole 5–7 mm long, 3–5 mm broad. Spikelets lanceolate, laterally compressed, ca. 35 mm long, 7–9 mm wide. Fruit a caryopsis, cylindric, 10–15 mm long, 3–5 mm wide, pericarp dark brown, rough.

Seed viability: Half year under normal atmospheric conditions; one year under storage at 1–6 °C.

Seed weight: 10 g ≈ 85–110 seeds covered by husks ≈ 130–150 de-husked seeds.

Seed germination: (1) Seeds (BS-0617) collected in 2010, received on 1st March 2011, and placed for germination in different media during the same month, 25–34 °C day, with diffuse light, 18–22 °C night, atmo­spheric humidity >70%, shoots emerged after 14 days, germination rate quite low (<20%), germinated best in moistened long coir fiber. — (2) Seeds (BS-0617) having been stored in a refrigerator for over 1 year, were placed on moistened tissue paper, on 8th January 2012, 22–26 °C day, with diffuse light, 11–19 °C night, atmo­spheric humidity >70%, the shoot of the earliest germinating seed emerged after 12 days, on 20th Jan., germination rate very low (<10%). — (3) Seeds (BS-0860, BS-0866) collected in Jan. 2016, and received by ธ. บ. in Feb. and Mar. 2016, respectively, performed a better germination rate.