Dendrocalamus sp. (CN: S)
Dendrocalamus sp. (CN: S) "D. fugongensis" / "D. tsiangii"
Distribution: THAILAND: introduced, in cultivation, rare. — CHINA.
Culm size: Not recorded, height expected to reach over 15 m.
Comments: Seeds from two provenances in southern China were received under two different Dendrocalamus names (BS-0662, BS-0667, see below), which turned out to represent the same yet unidentified species.
Specimens: BS-0662 [SSG] (living plant), raised from seeds, the seeds from FMXG, Yunnan, China, as "福贡龙竹 (fu gong long zhu), Dendrocalamus fugongensis", collected May 2011, and received 30 May 2011; BS-0667 [BBG, SSG] (living plants), raised from seeds, the seeds from the same source, as "黔竹 (qian zhu), Dendrocalamus tsiangii", collected May 2011 and Feb. 2012, and received 30 May 2011.
Characteristics: Rhizome pachymorph, short. Culms more or less erect, straight or somewhat zig-zag, branched from the basal nodes up. Young shoots dark purplish, emerge from June to September. Culm-internodes dark green and sparsely covered with short silvery velvety hairs when young, greenish-brown and somewhat rough when old; the length relatively short (18–28 cm on a 2.5 cm thick culm); walls rather thick. Culm-nodes with aerial root primordia on the basal and lower culm, with a ring of short white velvety hairs below the sheath scar; nodal ridge somewhat prominent. Branches several, the central one very dominant, 2 subdominant branches, and several thin ones. Culm-leaves (sheath + blade) longer than the internode, deciduous. Culm-leaf sheath leathery, dark purplish when young, straw-colored when dry, sparsely covered with brown to blackish short hairs; margin ciliate. Culm-leaf auricles and oral setae none. Culm-leaf ligule very long, 1–3 cm, lacerate, chaffy. Culm-leaf blade lanceolate, as long as the sheath (on the mid-culm), or 1/3–1/2 of the sheath length (on the lower culm), erect to deflexed, usually not caducous, occasionally reflexed and caducous when old. Foliage-leaves 7–11 (14) per branchlet. Foliage-leaf sheath glabrous, or with a few short hairs. Foliage-leaf auricles and oral setae none. Foliage-leaf ligule 1–2 cm long, reddish when young, entire, straw-colored and cleft when dry. Foliage-leaf blades lanceolate, glabrous above, minutely pubescent beneath when young, size large, to 44 × 10 cm, base rounded to attenuate, slightly asymmetric; midrib prominent; pseudopetiole 0.5–1 cm long.
Cultivation requirements: A strong grower, does well in full sun and moist soil.
BS-0662:
Seed viability: Unknown, viability is assumed to last at least several months.
Seed weight: 10 g ≈ 200–300 dried spikelets (husk-wrapped seeds).
Seed germination: Seeds (BS-0662) placed in moistened coir dust at 100%, in June 2011, atmospheric humidity >70%, coleoptiles emerged after 6 days, germination rate moderate (40–60%).
Comments: Characteristics of a young plant raised from those seeds do not match well with the description of Dendrocalamus fugongensis.
BS-0667:
Seed viability: Unknown, viability is assumed to last at least several months.
Seed weight: 10 g ≈ 130–180 dried spikelets (husk-wrapped seeds).
Seed germination: Seeds (BS-0667) placed in moistened coir dust at 100%, in June 2011, atmospheric humidity >70%, coleoptiles emerged after 6 days, germination rate moderate (40–60%).
Comments: Characteristics of a young plant raised from those seeds do not match with the description of Dendrocalamus tsiangii.
"Dendrocalamus fugongensis" (BS-0662): Seeds (left), young seedlings on coir dust (right)
"Dendrocalamus tsiangii" (BS-0667): Seeds (left), young seedlings on coir dust (right)
Comments: As the seedlings of BS-0662 and BS-0667 developed into plants over 2 m tall, it became apparent in September 2015 that both shared the same characteristics but still remained as an unidentified species in the genus Dendrocalamus. Unusual is the very long chaffy ligule, which should easily render identification. However, I could not find any Dendrocalamus species with such a long ligule listed in the Flora of China.
Dendrocalamus sp. (BS-0662): Culm-sheath with very long fringed chaffy ligule
Dendrocalamus sp. (BS-0667): Leafy branch with sheaths showing very long chaffy ligules