Phuphanochloa speciosa
Phuphanochloa speciosa Sungkaew & Teerawat., Kew Bull. 63 (4), 2009: 671.
Thai name: ไผ่ภูพาน (phai phu phan); local name ไผ่ข้าวหลามเปาะ (phai khao lam po). — BKF [#1368].
Distribution: THAILAND (North-East): Sakon Nakhon Province: Area of Phu Phan National Park; in deciduous dipterocarp forest, at about 500 m altitude, and a few other locations in north-eastern Thailand, endemic and rare. In cultivation in อ. กบินทร์บุรี Kabin Buri District of Prachin Buri Province, and in other regions of northern, north-eastern, and eastern Thailand.
Description: "Rhizomes short-necked pachymorph. Culms self-supporting, unicaespitose, straight and erect, about 5 – 10 m long, 3 – 5 cm in diam., walls 0.5 – 1 cm thick, smaller culms sometimes solid at basal internodes; internodes 25 – 30 cm long; young culms glabrous, white-waxy, mature culms green; nodes slightly swollen, all nodes without verticils of roots. Branches developing at all nodes to near base, several branches at each node, the primary one dominant, without aerial roots. Culm sheaths deciduous, occasionally tardily deciduous at basal nodes, coriaceous, 20 – 25 cm long by 12 – 17 cm wide, top obtuse, scattered with short pale hairs on the back, sometimes with a slight distal abaxial wrinkle; blades lanceolate, spreading to deflexed, 2 – 3.5 cm long, about 0.5 – 1 cm wide near the base, hairy at the adaxial base; auricles absent, or small rims, about 1 mm high, margins usually entire, occasionally slightly wavy, glabrous; ligule 2 – 3 mm high, margin toothed to bristly, bristles 2 – 5 mm long. Leaves 6 – 8 per branchlet; leaf-blades 10 – 15 cm long by 1 – 1.3 cm wide, abaxially hairy, apex acuminate, base acute, pseudo-petioles 0.5 – 2 mm long, secondary veins in 3 – 4 pairs, intermediate veins 5 – 6; auricles absent or of tiny rims bearing oral setae 1 – 3 mm long; ligule 1 – 2 mm high, apex obtuse, margin toothed; sheaths 4 – 5 cm long, hairy. [flowers and seeds described]". — S. Sungkaew & al. in Kew Bulletin vol. 63, 2008: 669-673 [#1096].
Images: Line drawing and photos in S. Sungkaew & al., Relationships between Phuphanochloa … and Its Related Genera.
Uses: Culm-internodes are used as flavor-enhancing cooking vessels for a Thai sticky rice dish called ข้าวหลาม (khao lam); culms are used for light broomsticks; young shoots are edible, of good taste; plants can be used to form a natural hedge that becomes impenetrable to livestock by intense branching on the lower culms. — Nana Bamboo สวนไผ่นานาพันธุ์ สวน, on Facebook, 14 Jan. 2021.
Comments: The species is adapted to drought periods, in which foliage leaves wither and roll up but remain attached to twigs. The species is also known to recover from forest fires.
Specimens: BS-0673 [-], BS-0673-1 [-] (living plants), northeastern Thailand: near อุทยานแห่งชาติภูพาน Phu Phan National Park in จังหวัดสกลนคร Sakon Nakhon Province, 30 May 2011, and 17 Sep. 2011.
Phuphanochloa speciosa (BS-0673, BS-0673-1), from left to right: (1) Young shoot, (2) upper part of a young culm-leaf, (3) rear view of a young culm-leaf attached to the culm, (4) dried culm-leaf, (5) typical branching on the mid and upper culm
Characteristics: Rhizome pachymorph, short. Culms erect, 11.5 m tall. Culm-internodes to 39 cm long, to 3.5 cm in diameter, thick-walled throughout, basally solid. Culm-nodes flat. Branch-buds rotund. Branches several, one somewhat dominant, slender branches on the lower culm usually down-curved, branches on the mid-culm and upper culm usually 3, subequal, relatively small in diameter, branches on the upper culm very slender, whip-like; the branching of the basal culm forms an impenetrable thicket. Culm-leaves early deciduous. Culm-leaf sheaths purplish when young, veins clearly visible when young and with a tessellating pattern. Culm-leaf auricles low entire rims, dark brown when young, adnate to the blade base margins, extending along the entire sheath apex and ending in an upward hook-like round bend. Culm-leaf blade small and narrow, spreading to reflexed. Foliage-leaf auricles absent or inconspicuous, bristles absent, or few and very short Foliage-leaf blades medium-sized to small, midvein not prominent.