Thyrsostachys siamensis Gamble (Gramineae)

Scientific name
Thyrsostachys siamensis Gamble
Family name
Gramineae (Syn. Poaceae)
Common name
Monastery bamboo, umbrella-handled bamboo (English); shamu dake (Japanease)
Local name
Nomai phai ruak
Densely tufted, sympodial bamboo. Culm erect or with arching tips, 8–14 m tall, 2–7.5 cm in diameter, smooth, greyish-green; internodes 15–30 cm long; nodes not swollen. Culm sheath 20–25 cm long, 10–20 cm wide near the base, narrowing towards the apex, persistent, pale to purplish-green, covered with scattered, pale, appressed hairs; blade narrowly lanceolate, 7-15 × 5-10 mm, erect, short-haired adaxially; ligule very short. Young shoots pale to purplish-green. Leaf blade narrow, linear, 7–14 cm × 5–8 mm, pale green, usually glabrous; sheath striate, white-haired along margins; ligule very short, entire, ciliate. Inflorescence borne terminally on leafy or leafless branches, many thin branchlets bearing bracteate clusters of few pseudospikelets; spikelet c. 15 mm long, comprising 1 empty glume, usually 2 perfect florets, and rachilla extension bearing a rudimentary floret. Caryopsis cylindrical, c. 5 × 2.5 mm, surmounted by a yellowish, glabrous, soft, long beak.
Traditional medicinal use
Functional constituents
Distributed widely in dry or semi-evergreen forests on poor soils. Grows in mixed deciduous and teak forests in northern and north-eastern Thailand; pure stands often occur in hill forests in central Thailand, at elevations of 300–400 m a.s.l., where the annual rainfall is 800–1,000 mm. Occasionally grown as a windbreak. Propagated by rhizome division in 1-year-old culms with rhizome, roots, and culm reaching at least 1 m. The rhizome pieces are placed in moist medium under 50% shade for 2–3 months or until new roots and shoots are sufficiently mature to be transplanted into the field at the start of the rainy season.
Bamboo shoots consist of 89.5 g water, 3.8 g protein, 0.3 g fat, 4.5 g carbohydrates, 0.7 g fibre, 1.0 g ash, 12.8 mg calcium, 40.2 mg iron, 0.2 mg phosphorus, 0.01 mg vitamin B1, 0.09 mg vitamin B2, and traces of vitamins A and C per 100-g serving. Their energy value is c. 140 kJ/100 g.
Young shoots are harvested during the rainy season, boiled and served with nam phrik (dipping sauces) or added to various dishes such as kaeng nor-mai (spicy bamboo shoot soup). However, most bamboo shoots contain high amounts of uric acid; therefore, those with joint pain should avoid any dishes containing bamboo shoots.
Aerial part
Dried stems