Rhopaloblaste augusta

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Rhopaloblaste
(roh-pah-loh-BLAHS-teh)
augusta (aw-GOO-stah)
Post-117-1171417910.jpg
Nong Nooch TBG, Thailand 08/2006.
Scientific Classification
Genus: Rhopaloblaste
(roh-pah-loh-BLAHS-teh)
Species:
augusta (aw-GOO-stah)
Synonyms
None set.
Native Continent
Oceania
Oceania.gif
Morphology
Habit: Solitary
Leaf type: Pinnate
Culture
Survivability index
Common names
Nicobar Majestic Palm

Habitat and Distribution

Rhopaloblaste augusta is found on; Nicobar Islands, Camorta (Kamorta), Peninsular
Hilo mall, Hawaii. Photo by Geoff Stein.
Malaysia & Singapore, the Moluccas, New Guinea & the Solomon Islands. In lowland rain forest.

Description

Robust, mid-storey, solitary palm bearing up to 11 leaves in the crown. Stem to 25 m tall, 20 - 30 cm in diam., surface brown, becoming grey with age, leaf scars conspicuous. Leaf sheath 48 - 60 cm long, greyish brown, lepidote tomentose; crownshaft 50 - 61 cm long, 30 - 40 cm in diam.; petiole short, 8 - 10 cm long, concave on adaxial and rounded abaxially; rachis 2 - 4 m long, with dense interlocking pale whitish brown scales on the abaxial surface especially when young, but becoming brownish black with age, less dense whitish brown scales on the adaxial surface; leaflets 90 - 100 each side of rachis, borne 3.5 - 4 cm apart, in one plane, pendulous, middle leaflet 60 - 70 x 2 - 3 cm, sublinear, acuminate, tapering acutely and bifid at the apex, discolorous, with sparse ramenta present along the mid-veins of the pinnae on the abaxial surface, and with rusty dark brown membranous scales on the adaxial surface, persisting at the base of the pinnae. Inflorescence 40 - 60 cm long, branched to 3 orders, primary branches 14 - 16, 45 - 56 cm long, basal pair of primary branches strongly recurved; prophyll 40 - 45 cm long, with sparse greyish brown scales; peduncle 4 - 5 cm long; rachillae moderately slender, 36 - 43 cm long, 2.9 - 3.8 mm diam., dull greenish brown. Staminate flower symmetric, 6 - 6.8 mm long, 4 -4.8 mm in diam.; sepals 2.5 - 3 x 2.6 - 2.8 mm, strongly imbricate, rounded; petals 4 - 4.5 x 3 - 3.5 mm, broadly elliptic; stamens 3.2 - 3.5 mm long, filaments 2 - 2.1 mm long, connate at the base, anthers 3 - 3.2 mm long, 0.8 - 1 mm diam.; pistillode conical, 4.3 - 4.5 mm long, 1 - 1.1 mm in diam. at the base. Pistillate flower 4 - 4.1 mm long, 3.8 - 4 mm diam., borne throughout the rachillae; sepals 3.5 - 3.8 x 3 - 3.5 mm, rounded, margin on the apex serrate; petals 3.6 - 4 x 2.8 - 3 mm, broadly elliptic; staminodes 4, lobes 0.8 -1 x 0.9 - 1 mm, acute at the apex; gynoecium 2.8 - 3.1 mm long, 1.2 - 1.5 mm in diam., ovoid. Fruit 22 - 26 mm long, 10 - 14 mm in diam., elongate ellipsoid, orange to red when ripe; cupule of persistent perianth 7 - 8 mm long. Seed 17 - 20 mm long, 9 - 11 mm in diam., elongate-ellipsoid, brownish, with a conspicuous impression over the hilum; testa brown. (R. Banka and W.J. Baker. 2004)/Palmweb. Editing by edric.

R. augusta is distinct in its medium-sized, elongate, ellipsoid fruits, moderately slender fruit- bearing rachillae and inflorescences branched to three orders. It is a promising ornamental species, grown in botanical gardens for its bright fruits and attractive foliage. (R. Banka and W.J. Baker. 2004)/Palmweb.

Culture

Sunny, moist, but well drained position. The most cold tolerant of the Rhopaloblaste, but still requires a warm, sheltered spot in the sub-tropics. Cold Hardiness Zone: 10b

Comments and Curiosities

Uses: Of all the species of Rhopaloblaste, R. augusta is perhaps the most widely grown species for ornamental purposes. (R. Banka and W.J. Baker. 2004)/Palmweb.

"Tall (100') solitary pinnate species from Nicobar Islands. It has a light grey fuzzy crownshaft (that I have never really seen since all palms I've seen are so tall I can barely even see a crownshaft). The leaves are 12' long with a subtle arch and have 2' long pendant leaflets-great looking sillouhette. Very tropical in its needs. (Geoff Stein)

In cultivation, this 30 m (100 ft.) tall and truly majestic palm from the tiny Indian Nicobar Islands north of Sumatra in the Andaman Sea is still poorly known. For warm subtropical and tropical climates, it has all the features you could possibly ask for in a successful landscaping plant: tall, smooth tunk; long crownshaft; full crown of long, spreading, self-cleaning, unarmed leaves with long, gracefully drooping leaflets; and showy reddish fruit. Germination is easy and subsequent growth rates are fast as long as there is sufficient moisture in the ground. (RPS.com)

External Links

References

Phonetic spelling of Latin names by edric.

Special thanks to Geoff Stein, (Palmbob) for his hundreds of photos, edric.

Special thanks to Palmweb.org, Dr. John Dransfield, Dr. Bill Baker & team, for their volumes of information and photos, edric.

Glossary of Palm Terms; Based on the glossary in Dransfield, J., N.W. Uhl, C.B. Asmussen-Lange, W.J. Baker, M.M. Harley & C.E. Lewis. 2008. Genera Palmarum - Evolution and Classification of the Palms. Royal Botanic Gardens, Kew. All images copyright of the artists and photographers (see images for credits.

Banka, R. & Baker, W.J. 2004. A Monograph of the Genus Rhopaloblaste (Arecaceae). Kew Bulletin, Vol. 59, No. 1, pp. 47-60.


Many Special Thanks to Ed Vaile for his long hours of tireless editing and numerous contributions.

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