Pseudosasa sp. (TH: Chiang Mai, Loei)
Pseudosasa sp.
Thai name: No known records.
Distribution: THAILAND (North): Chiang Mai Province: Doi Inthanon; (North-East): Loei Province; wild (native or naturalized) and cultivated.
Local distribution: In cultivation by the Royal Project at Doi Inthanon, Doi Ang Khang, and Mae Hia, both Chiang Mai Province. (S. Sungkaew & al., 2008: 11 [#1073])
Culm size: Height about 3–4 m, diameter to 1 cm.
Characteristics (based on BS-0364 and BS-0411): Rhizome leptomoph. Culms terete, flattened above branches, erect below, nodding above, usually unbranched on the lower and mid culm. Culm-internodes green, glabrous, smooth, with a ring of whitish wax below nodes when young, early fading, thick-walled (lacuna less than 1 mm by a diameter of 6 mm). Culm-nodes with prominent nodal ridge; infranode pronounced, green, smooth. Branches subequal, thinner than the main culm, typically 3 on the mid-culm nodes, or 4–6 on the upper nodes. Culm-leaf sheath on unbranched nodes usually late deciduous, occasionally persistent or loosely attached and decaying on the culm, early deciduous on branched nodes, whitish to light straw-colored and glabrous when dry, with scattered tiny blackish dots, about one-half to one-third (one-fourth) as long as the internode. Culm-leaf auricles tiny, reflexed, oral setae long, both early caducous. Culm-leaf ligule 1 mm long, convex. Culm-leaf blade small, triangular, reflexed, not erect, and early caducous. Foliage-leaves (3) 4–6 (7) per branchlet. Foliage-leaf sheaths green, or yellowish green to brownish green, glabrous, apex concave, on both sides with several, usually straight up to 6 mm long pale bristles. Foliage-leaf auricles inconspicuous or none, with several, straight or twisted up to 6 mm long pale bristles. Foliage-leaf ligule inconspicuous. Foliage-leaf blades 12–23 (29) × 2–3.5 (4) cm, tough, slightly asymmetric, mid-green to dark green above and not shiny, green to bluish-green beneath, tessellate, glabrous on both surfaces; base rounded to wedge-shaped; apex attenuate; margins antrorsely scabrous; midrib prominent beneath, yellowish-green; pseudopetiole 5–7 mm long, glabrous. Flowers and seeds are unknown.
Uses: Not recorded.
Cultivation requirements: Easy and fast-growing; in part shade to full sun, normal moisture-retentive to moist with good drainage.
Provisional identification: This could be a species of Pseudosasa subg. Sinicae, a subgenus that is characterized by usually three branches per node and deciduous culm sheaths. In the overall appearance of the currently still immature plants, the unidentified species is similar to Pseudosasa japonica (subg. Pseudosasa), which has a solitary branch per node and persistent culm sheaths. The unidentified species has short culm sheaths, whereas in Pseudosasa japonica, culm sheaths are almost as long as the internode. The culm sheaths of the unidentified species have bristly auricles, whereas these are lacking in Pseudosasa japonica. However, I am not yet convinced that the unidentified species belongs to Pseudosasa. Its vegetative parts resemble Sinobambusa tootsik. The unidentified species shows flattened internodes above branches, which are characteristic of Sinobambusa. The characteristics need to be observed in more detail when the unidentified species reaches a mature height, and the young shoots of the unidentified species also need to be observed.
Pseudosasa sp. pop. Doi Inthanon
Distribution: THAILAND (North): Chiang Mai Province: อุทยานแห่งชาติดอยอินททน์ (Doi Inthanon National Park), at high elevations of Doi Inthanon, wild, also planted at the top of the mountain (2,565 m). It is not clear if the species is native. More likely, it was introduced a long time ago and became naturalized. It is kept in cultivation at the Royal Project Bamboo Collection site at Mae Hia, Chiang Mai.
Specimens: BS-0364 [BBG] (living plant), Bamboo Center, Royal Project Foundation ศูนย์ไผ่ มูลนิธิโครงการหลวง T. Mae Hia, A. Mueang, Chiang Mai ต. แม่เหียะ อ. เมือง จ. เชียงใหม่, northern Thailand, cult., received as "Pseudosasa japonica", Dec. 2009, earlier collected from a wild population at a high elevation of Doi Inthanon, อุทยานแห่งชาติดอยอินททน์ (Doi Inthanon National Park), Chiang Mai Province. MH-012 (living plants), planted on the site of the Bamboo Center, Royal Project Foundation, Mae Hia.
Characteristics: Branches turn to dark maroon.
Pseudosasa sp. from Doi Inthanon, BS-0364: Branches on lower culm
Pseudosasa sp. cl. Loei
Distribution: THAILAND (North-East): Loei Province.
Specimen: BS-0411 [BBG] (living plants), received as "ไผ่หลอด (phai lot)", collected from a widespread stand in a resort in Pai, Mae Hong Son Province, northern Thailand, by ธ. ล. in Jan. 2010, said to originate from the wild in Loei Province, north-eastern Thailand.
Characteristics: Branches green, or brownish green.
Comments:
(1) It was said that the rhizome/roots release an odor.
(2) The Thai common name, phai lot, was applied to Schizostachyum mekongensis, syn. Neohouzeaua mekongensis, but the plant does not meet the characteristics of this species as described in KewGrassBase.
(3) Plants from Doi Inthanon and Loei seem to represent the same species, but it is currently not confirmed that it is naturalized Pseudosasa japonica.
Pseudosasa sp. pop. Phitsanulok
Distribution: THAILAND (Central): Phitsanulok Province.
Comments: A Pseudosasa species is suspected to occur in Phitsanulok (Classification of Bamboo, 2012 [#1223]), but no further information is available.