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Volume 41, Number 3
Summer 1987

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The Non-Malesian Rhododendrons, Section Vireya
Dr. R.M. Withers
Hawthorne, Victoria, Australia

Reprinted with permission from The Rhododendron, the Journal of the Australian Rhododendron Society, December 1986.

        In a letter dated August 8th, 1985, the late Mr. John Womersley wrote that he had drawn a map showing the distribution of nine Vireya species growing exclusively outside Malesia in the Northern Hemisphere, and planned to write a paper discussing the botany and distribution of these species; in his opinion it seemed obvious from the map that there must be more species of Vireya in that area. As several of the species are in cultivation in Australia, John asked me if I would like to join him as co-author to cover the horticultural aspects for the relevant species.
        John was not able to complete the article, but I am very grateful to Mrs. Mary Womersley for letting me have John's notes on a wide range of rhododendron topics on which he was working, including his notes on the Non-Malesian Vireyas, so that I am now in a position to do my best to complete the article as John had planned.
        To the species shown on the map, R. vaccinioides, R. asperulum, R. insculptum, R. emarginatum, R. santapaui, R. kawakamii, R. sororium, R. chevalieri, and R. triumphans, I think that John intended to add another 2 species, R. malayanum and R. lochiae, although that of course, occurs in the Southern hemisphere.

Subsection PSEUDOVIREYA
  1. R. vaccinioides Hook, f., Rhod. Sikkim Himal., pt. ii, p. 3, syn. R. sinovacciniodes Balf. f. & Forrest.
  Locality: India, N.E.F.A., Darjeeling; Sikkim; South East Tibet.
  Altitude: 1800 - 2200 m. [Sikkim], 2700 - 3800 m. [Tibet].
  Habit: a small epiphyte on trees and on rocks; branchlets densely rugose with wart-like glands; winter leaf-bud-scales persistent for at least a season.
  Leaves: rather scattered, spathulate-oblanceolate, emarginate and mucronate, about 2 cm. long, very loosely punctate-scaly below, without visible lateral nerves.
  Inflorescence: 1-2 flowered, terminal; flower stalks 1-2 cm. long, scaly.
  Flowers: Lilac-pink, or white tinged with pink.
  Calyx: lobes 5, oblong 3 mm. long, sparsely scaly.
  Corolla: campanulate, 7 mm. long, 5 lobed, very slightly scaly outside.
  Stamens: 10, exserted, pubescent in the middle.
  Ovary: ovoid, scaly, gradually passing into the thick short glabrous style.
  Capsule: 2.5 cm. long, opening from the top; seeds minute, with a long tail at each end 6 mm. long.

R. vaccinioides has been introduced into cultivation but is very rare. It was observed in flower in the glasshouse at Edinburgh Botanic Gardens during the 2nd International Rhododendron Conference in May 1982. At least one person is growing this species, and flowering it in the U.S.A. Dr. John Rouse was fortunate in obtaining seed from the U.S.A. in December 1983. Some seed was sown from which 8 seedlings with low vigour were obtained. Of these only 2 have survived. They are 30-40 mm. in height but are not growing well. The remaining seed was sown in May 1984. Fifteen seedlings were obtained, but all died.

Subsection PSEUDOVIREYA
  2. R. asperulum, Hutch. & Ward, The Species of Rhododendron, The Rhododendron Association, 1930, p. 818.
  Locality: Southern Tibet; Seinghku Wang (28 5' N., 97 30' E.) on alders and other trees and boulders in open pastures [Ward, 6801 type]; Valley of the Di Chu, 2300m. [Ward, 7163].
  Habit: an epiphyte on alder trees or growing on boulders; one-year old and young shoots very closely scabrid with warts, reddish.
  Leaves: obovate-oblanceolate, emarginate and mucronate, 2.5 -3.8cm. long, 1.2 - 1.6cm. broad, leathery, loosely glandular-punctate below, the glands 2-3 times their own diameter apart, with distinct lateral nerves impressed on the upper surface.
  Inflorescence: 3 flowered, terminal flower stalks about 1.2cm. long, slightly warted.
  Flowers: pale flesh pink, with orange anthers.
  Calyx: deeply lobed, lobes oblong, 3mm. long, loosely-scaly outside.
  Corolla: shortly campanulate, 8mm. long, 5-lobed, slightly scaly outside.
  Stamens: 10, exserted, pubescent in the middle third.
  Ovary: ovoid, scaly, gradually passing into the thick glabrous style.
  Capsule: 2.5cm. long, opening from the top downwards; seeds minute, with a long thread-like tail at each end.

Not in cultivation.

Subsection PSEUDOVIREYA
  3. R. insculptum, Hutch. & Ward, The Species of Rhododendron, The Rhododendron Association 1930. p. 821.
  Locality: Southern Tibet; Seinghku Wang (28 5' N., 97 30'E.). Temperate rain-forest at 2,000 - 2,300 m. (Ward 6735 type.).
  Habit: an epiphyte; branchlets rough scaly when young, the winter bud scales early deciduous.
  Leaves: whorled, broadly obovate-spathulate, emarginate and mucronate at the apex, gradually narrowed to the base, about 3.8 cm. long, with about three pairs of much impressed nerves on the upper surface, punctulate-lepidote below.
  Inflorescence: axillary, 1 flowered; flower stalks 2.5 cm. long, angular, with a cluster of persistent scales at the base.
  Flowers: bright orange, with brownish-red anthers; style orange.
  Calyx: small, shortly undulately 5-lobed, scaly outside.
  Corolla: broadly campanulate, fleshy, 1.3 cm. long, 5-lobed, loosely covered with small scales outside, pubescent inside the top of the tube.
  Stamens: 10, exserted, 5 long and 5 short, pubescent to above the middle.
Ovary: 5 celled, oblong-ellipsoid, densely scaly and softly pubescent; style as long as the ovary, stout, glabrous, gradually expanded upwards, sharply bent down between the two lower corolla-lobes.
Capsule: about 2.5 cm. long, valves opening from the top, thin, sparsely covered with very small scales.

Not in cultivation.

Subsection PSEUDOVIREYA
  4. R. emarginatum, Hemsl. & Wilson, Kew Bulletin (1910), p. 118, syn. R. euonymifolium Levl. and R. poilanei Dop, Fl. Indo-Chine 3 (1930) 739.
  Locality: Yunnan, Mountains S-W of Mengtsze, 2,000 m.a.s.l.; Kwei-Chow, Pinfa on rocks (R. euonymifolium).
  Notes: see Sleumer, Blumea, 1958, Supple, IV p. 47.
  Habit: bush, 60 cm. high (Henry); branches spreading (Henry),? prostrate, twiggy, verruculose.   Leaves: pseudo-verticillate, obovate, exluding petioles 3-4 cm. long, 1.5-2 cm. broad, rounded, emarginate, mucronulate, base narrowed to the petiole; upper surface dark green, sparsely lepidote when young; lower surface pallid, lepidote; midrib and secondary veins immersed above, very prominent beneath; petioles 3-5 mm. long, lepidote.
  Buds: ovoid, acute; scales ovate, acute, ciliolate, very sparsely lepidote.
  Flowers: solitary or in pairs (always?), yellow (Henry), about 1cm. across; pedicels erect, 2 cm. long, lepidote.
  Calyx: annular, 5 toothed; teeth minute, unequal, obtuse.
  Corolla: campanulate, 5 lobed, lepidote outside; lobes short, spreading, rounded.
  Stamens: ten, included; filaments broad, about 5mm. long, villous about the middle, glabrous at base. Pistil over-topping stamens.
Ovary: 2 mm. long, furrowed, densely lepidote. Fruit not seen. Very distinct from all other Chinese species.

Not in cultivation.
From the material before us we think the species may be prostrate in habit. - E.H.W.

Non-Malesian Vireyas map

Subsection PSEUDOVIREYA
5. R. santapaui, Sastry et al., Journ. Bombay Nat. Hist. Soc., Vol. 65 (3).
Locality: India, N.E.F.A. Subansiri.
Reprinted from: Journal Bombay Natural Hist. Society, Vol. 65 (3).
Allied to R. kawakamii Hayata, from which it differs in the shape and apex of the subverticillate leaves; 2 flowered inflorescence; densely scaly ovary; much longer, scaly capsule. Epiphytic twiggy shrub, 0.5 - 1.5 m. high; twigs slender, spreading terete, scabrid; young shoots densely scaly; scales white, circular, c. 0.25 mm. in diameter, deciduous, internodes 3-8.5 cm. long; cataphylls 1-2 below the leaves, c.5 mm. long, subulate, scaly deciduous. Leaves subverticillate, 8-12 (15) in a whorl, subsessile, elliptic or elliptic-lanceolate, 2-4.5 x 0.5-2.0 cm., coriaceous; base attenuate, apex acute - subobtuse, shortly apiculate, young leaves densely scaly on both sides; old leaves dark green, rugulose above, pale green, sparsely brown punctate-scaly beneath; margins entire, hyaline, recurved when dry; midrib prominent, impressed above, ridged beneath; lateral nerves 3-4 pairs, impressed above, obscure beneath; petiole c.3mm. long. Inflorescence terminal, umbellate, 2 flowered, bracteate, bracts many, ciliate, 5-8 x 3-6 mm. outer small, ovate-lanceolate, long aristate, inner large, deltoid, cupular, glumaceous, cuspidate; pedicels 1-2 cm. long, slender, slightly curved, densely scaly. Flower buds white, pyriform, c. 12 mm. long. Calyx saucer-shaped, c. 1.5 mm. long, c. 2 mm. broad, densely scaly outside, undulately 5-toothed, persistent, Corolla waxy-white, fleshy, campanulate, 1.5-2.5 cm. wide at mouth; tube 3.5 - 8 mm. long, 3-6 mm. in diameter, sparsely scaly outside, glabrous inside, pilose at throat; lobes 5, sparsely scaly outside, rounded or broadly oblong, subacute, or obtuse, 6-8 mm. x 5-8 mm., erect gradually becoming reflexed. Stamens 10, subequal, c. 12 mm. long, filaments white-pubescent in the middle; anthers creamy. Ovary ovoid or ovate-oblong, c. 5 x 2.5 mm., 5-ridged, densely scaly; style stout, c. 5 mm. long, declined, slightly enlarged upwards, glabrous; stigma truncate; disc annular, 10 lobed, glabrous. Capsule oblong, c.3 cm. long slender, straight, thin-walled, 5 celled, sparsely scaly, long pedicellate pedicel as long as capsule.

Holotype, A.R.K. Sastry 45720, collected from Begi, c. 1540m. alt. in Subansiri district, on May 23, 1966, is in Central National Herbarium (CAL). Paratypes, A.R.K. Sastry 42112 A-C (A&B in fruit, C in flower) collected in between Saling-Hakhetari, c. 2300 m. alt. in Subansiri district, on April 21, 1965, are in the Kanjilal Herbarium, Shillong (ASSAM).

This new species is dedicated to Rev. H. Santapau, as a token of our regard and appreciation of his devoted service in the cause of taxonomic research and promotion of floristic exploration in India.
        This rare epiphytic species was first collected in late fruiting stage (Sastry 42112A&B,C&H 459) from Subansiri during April 1965 by a joint expedition of Botanical Survey party of A.R.K. Sastry and S.K. Kataki and the 3-member British team of Peter and Patricia Cox and P. Hutchison. The latter have noted this find in their account of the expedition in The Rhododendron and Camellia Year Book (1966:73). A live plant (Sastry 42112 C) was introduced into the "Woodlands" Compound, Botanical Survey of India, Eastern Circle, Shillong, and flowered during September 1965. A preliminary study showed this to be a new species, allied to R. kawakamii Hayata from Formosa. On a subsequent exploration during May 1966, a careful search for more plants of this species yielded just two in the vicinity of Begi, which were introduced and reared in "Woodlands" in as near a natural habitat as possible (except for its epiphytic nature). One of these flowered during July 1967 (45720) enabling confirmation of the earlier tentative inference of its being a novelty. In the meanwhile Mr. Peter Cox also reported in a letter that plants of this species introduced in 1965 into his garden in Glendoick, Perthshire, flowered about September 1967.
        Flowering in this plant is a protracted process, the young flower buds covered with bracts appearing in October 1966, and ultimately flowering in July 1967. The bracts fall off, revealing the white pear-shaped flower buds which later on open into a waxy white campanulate corolla, with the prominently ringed anthers protruding in its centre. The corolla lobes later become reflexed and after anthesis the entire corolla readily drops off. Though lacking the flamboyance of large flower trusses of other rhododendrons, this midget shrub with its young shoots pinkish in contrast to the older dark green foliage and the geminate waxy white starry flowers, promises to be an elegant introduction.
        Members of the Australian Rhododendron Society became interested in R. santapaui when they read the article by Mr. Peter Cox in The Rhododendron and Camellia Year Book (1968: p. 202), describing a possible new species of rhododendron in the Vaccinioides Series. Mr. Cox kindly sent to the Society a small quantity of seed which was sown in June 1970. The seedlings were to flower a number of years later with very attractive, although small, pure white waxy flowers, set off by the browny-red anthers and red stigma.
        It has proved to be very difficult to cross R. santapaui with other Vireya species, the one exception being with R. kawakamii within the same Subsection Pseudovireya, the successful crossing being made by Dr. John Rouse.
        The cross R. santapaui x R. kawakamii var. flaviflorum was made May 1, 1984. Seed was sown September 12, 1984 with 51% germination. Seedlings initially had low vigour, but are now growing well. Owing to the fact that no seedlings have yet flowered, hybridity cannot be confirmed.
        R. santapaui is self compatible, but apart from the cross with R. kawakamii var. flaviflorum, no hybrids have been obtained with any other rhododendron species.

R. santapaui
R. santapaui
Photo by Dr. John Rouse

Subsection PSEUDOVIREYA
6. R. kawakamii, Hayata, Journ. Coll. Sci. Univ., Tokyo 30 (1) 171, 1911, var. flaviflorum Liu & Chuang, Quart. Journ. Taiwan Mus. 13 (1960) p. 64, t.2.
Locality: Taiwan (Formosa), Mount Yushan; Mt. Morrison; Mount Ali-shan, alt. 1550 - 2600 m.
Epiphytic shrub, 0.3 - 1.3 m. tall; branches numerous, slender, often tortuous, glabrous, gland-dotted; bud-scales acute, ciliolate, punctate. Leaves subsessile, coriaceous, glabrous, numerous, clustered into remote false verticils, spathulate to oblanceolate or obovate, 1.5 - 5 cm. usually 2.5 - 4 cm. long, 0.8 - 3 cm., usually 1.5 - 2 cm. wide, rounded, mucronulate, base narrowed, upper surface dark green, lower paler, often yellow-brown, copiously punctate, margin slightly recurved, midrib and secondary veins impressed above, raised below; petiole 0.2 -0.5 cm. long, winged. Flowers racemose-umbellate, 5 or more; pedicels spreading, 2 - 2.5 cm, long, sparsely gland-dotted; calyx saucer-shaped, 5-lobed, lobes irregular, oblong lanceolate or triangular, 1 - 2 mm. long, glandular-ciliolate; corolla glandular punctate, rotate-campanulate, 1 cm. long, 1.2 cm. broad, 5 - lobed, lobes broad oblong, rounded, stamens 10, shorter than the corolla, unequal, filaments villose at the base, anthers oblong, 2.5 mm. long pistil shorter than the corolla, ovary ovoid, 2 mm. long pubescent, style curved, glabrous, stigma capitate. Fruit oblong-ovoid, about 1.2 cm. long, sparsely villose, dehiscing to base, margins of valves waved.
        On and around Arisan between 1550 and 2600m. above sea-level, this is a very common epiphyte. It is particularly abundant in the forests of Chamaecyparis formosensis Matsum, growing high up in the forks and on the branches of these gigantic trees. But it is not confined to this conifer being found epiphytic on many kinds of trees in these rain forests. It is a bushy plant, from 60 cm. to 1.5 m. high and broad, with numerous often gnarled and lichen-clad branches. I did not see it in bloom and my description of the flowers is from Hayata's original account. The species, as Hayata points out, is closely related to R. emarginatum Hemsl. & Wils. which is native of south Yunnan. These with which must be associated Rhododendron vidalii Rolfe and several other Philippine and Malaysian species with their cuneate, spathulate to obovate, verticillate leaves, punctate on the under surface, form a little group distinct from other sections of the vast genus. All are tropical and many of them epiphytic, the last from necessity rather than choice. None are in cultivation.

Rhododendron kawakamii Hayata was discovered in the neighborhood of Arisan, at an elevation of 2300 m. above sea-level in 1906 by Messrs. T. Kawakami and U. Mori.
        Flowers: The flowers have since been described as being pink or white in colour with the var. flaviflorum having smaller yellow flowers. The pink or white forms are not in cultivation to our knowledge.
        In March 1969 the Rhododendron Venture in Taiwan was commenced by Mr. John Patrick and The Australian Rhododendron Society purchased a share. Seed of the yellow form of R. kawakamii was collected on November 11, 1969 at Rrwanping below Alishan at 2000 metres. Some of the seed was forwarded to the Society and sown on December 10, 1969. The seed germinated well and the seedlings were to flower a number of years later. Several plants of R. kawakamii var. flaviflorum were also forwarded to the Society and this species has since proven to be very hardy under our conditions.
        Like its close relation R. santapaui, R. kawakamii var. flaviflorum has been very difficult to cross with other rhododendrons, and the only success has been obtained by Dr. John Rouse in crossing those two species. The cross R. kawakamii var. flaviflorum x R. santapaui was made on December 7, 1982 and the seed sown on March 5, 1983. The seedlings had low vigour but are now growing well. As the seedlings have not yet flowered, like the reciprocal cross, hybridity cannot be confirmed.
        Both R. santapaui and R. kawakamii var. flaviflorum have grown well when grafted on to 'Fragrantissimum' understocks, and both have also grown well when grown on Vireya hybrid understocks.
        The fact that it has been impossible to cross these two species with species in the Subsection Pseudovireya native to the Malesian area or with species of Vireya rhododendrons in other subsections might suggest that they are not Vireya rhododendrons and it may follow that a future revision of the genus Rhododendron will find them placed in another section other than Vireya.

R. kawakamii var. flaviflorum
R. kawakamii var. flaviflorum
Photo by Dr. John Rouse

Subsection PSEUDOVIREYA
  7. R. sororium, Sleumer, Blumea, 1958, Suppl. IV, 47 - 48
  Locality Tonkin, Lao - Kay; alt. 1400 - 1700m.
  Shrub, branchlets about 2 mm. in diam., terete, covered with small stalkless scales near internodes 1 - 2, but soon becoming entirely glabrous.
  Leaves arranged in pseudowhorls of 5, of variable size, obovate with apex rounded or minutely shallowly notched. Finely pointed glands in the base of the petiole, cuneate and somewhat decurrent, leathery, richly olive green above, paler below. At maturity glabrous above, but earlier covered with moderately thick small scales. Leaves 2.5 - 4.5 cm. long, 1 - 2 cm. wide, margins a little revolute, lateral 2 - 3 veins curved in both directions, above sunken, below slightly raised.
  Petioles flattened, about 3 - 5 mm. long, 1.5 - 2 mm. thick.
  Flowers solitary, rarely paired. The backs of the bud scales have long straight close pressed glossy hairs, the margins covered with dense white hairs. The outer bud scales are broadly ovate, a little rounded or blunt, the inner broadly ovate, somewhat acuminate, 1 cm. long and 0.5 cm. wide.
  Pedicels densely covered with small scales, at flowering 1.5 - 2, at fruiting 2 - 2.5 cm. long, about 0.8 mm. when the outer layer has been shed.
  Calyx oblique about 3 mm. diam., lobes blunt continuously, 1 mm. long, frequently ill-defined.
  Corolla slightly fleshy, colour not known, broadly trumpet shaped, with expanded corolla lobes, about 1.4 cm. long when fully developed. Tubes about 8 mm. long, about 4mm. diam., externally densely scaled, internally somewhat white with long weak hairs.
  Lobes obovate, externally loosely covered with small scales, internally glabrous, about 6 - 7 mm. long, about 4 mm. wide.
  Stamens 10, alternately 10 and 8 mm. long, filaments linear, flattened near the base and glabrous at the apex.
  Anthers linear about 3 mm. long, 0.7 wide.
  Discs glabrous.
  Ovaries cone shaped with style very abrupt, densely covered with small scales, about 5 mm. long, 2.5 mm. diam., style columnar, upwards thickened, glabrous, stigma abruptly truncate.
  Capsule not seen when quite mature obliquely oblong, about 1.7 long, 0.3 cm. wide, style thick glabrous 5 - 6 mm. long.
  Translated from the Botanical Latin by R.M. Withers.
  Not in cultivation.

Subsection EUVIREYA Series JAVANICA
  8. R. chevalieri
  Locality: South Vietnam (Annam), near Honba, prov. Nha-Trang, alt. 1500 m.
Rhododendron chevalieri P. Dop in A. Chevalier Rev. Bot. Appliq. et d'Agric. Tropic. IX annee, No. 92, April 1929, p.256, pi. X.
  Epiphytic shrub, 1-2 m., the young plants are anchored by fusiform roots in the humus covering the bark of trees; much older roots very branched. Branches slender, erect, ash grey, very gnarled. Young growths glabrescent, with scattered fawn hairs, scales adpressed, very thin.
  Leaves arranged in falsely vertidilate clusters of 4-7, coriaceous-fleshy, oblong, wedge shaped, decurrent at the base to the petiole, narrowed, pointed at the apex, 4 -4.5 cm. by 1.5 - 2.5 cm; upper surface glossy, finely rugose, glabrous, with some scattered fawn hairs, scattered glands very thin. Lower surface pale with black pitting, scales very thin and with adpressed glandular hairs. Median nerve depressed above, somewhat prominent below, secondary and reticulate venation invisible.
  Petiole 8 - 12 mm., finely glandular on the surface.
  Flowers in terminal sessile umbels of 3 - 5 flowers; pedicels reflexed, finely covered with whitish scales on the surface, 10 - 12 mm. long.
  Calyx tube and disk 3 - 4 mm. long with glandular points and obsolete lobes.
  Corolla entirely pale yellow, funnel-shaped or like an expanded bell; glabrous within and without, 2.5 cm. long, lobes all large 3 - 3.5 cm. across (diameter) at maturity, these 10-12 mm. and the largest 15 mm., broadly oval, often a little folded and notched at the summit.
  South Annam: forest edges near Honba, 1500 m. alt. on the trunks and branches of old mossy trees.   Flowering Sept. 1, 1928*. Appears related to R. triflorum Hook. f.

* This is the year of collection as published but is in conflict with the date of 1918 given for R. triumphans also collected in the same locality. Only an examination of the actual specimens, presumably in Paris would reveal the correct year.
  Translated from the original French, J.S. Womersley, July 1985.
  Not in cultivation.

Subsection EUVIREYA Series JAVANICA
  9. R. triumphans
  Locality: Vietnam (South Annam), Honba, Prov. Nha-Trang; alt. 1200-1500m.
Rhododendron triumphans Yersin & A. Chevalier Rev. Bot. Appliq. et d'Agric. Tropic. IX annee, No. 92, April 1929, p.256, pi. XI.
  Shrub, 1.5 - 2 m. high, stem slender, 15 mm. diameter, roots often swollen, fusiform, 3 - 4 cm, thick.
  Bark cinder-grey; buds very large, scales (perulae) pale green, glabrous, oval, pointed; young growth with small fawn-coloured hairs and scales.
  Leaves alternate, grouped at the ends of the branchlets, entire, coriaceous, slightly folded and undulate in the middle, lanceolate, usually attenuate at both ends, very pointed at the apex, 15 - 20 cm. by 6 - 8 cm. Upper surface very glossy dull green, in the young stage with scattered fawn scales (hairs and scales visible with a magnifying glass, disappearing with age, and below with small punctations, close, persistent, hairs glandular). Median nerve very prominent above in the lower third; secondary nerves 10-14 pairs, visible on both faces but only slightly visible, two nerves conjunct, comprising infrequently connecting tertiary nervation, very slender (fine).
  Petiole robust, 18 - 25 mm. long, subcylindric, in the young stage with scattered fawn hairs, disappearing with age, almost always reddish in colour.
  Inflorescence a terminal corymb of 5 - 9 flowers, each very large and of a beautiful brick-red (cinnabar) colour, non-scented, the whole forming a head of 25 cm. in diameter, the tube of the flower at an angle of 120 with the pedicel.
  Pedicels of the flowers erect, 2.5 - 4.5 cm. long, cylindrical, greenish red, glabrous, at the base with very fugacious bracts, swollen at the apex and terminated by a very reduced calyx, not easily seen, glabrous.
  Corolla entirely glabrous, 8 cm. long, 10 cm. diameter, spread in a much widened funnel-shape at the apex and narrowed at the base into a sub-pentagonal tube with five large lobes projecting to 1 mm. by 1.5 mm., lobes (corolla) 5 to 4 cm. long and wide, rounded at the apex, overlapping at the base one on the other. Inside of the tube a washed out whitish-red in the throat.
  Stamens 10, reddish-carmine, 4 - 4.5 cm. long, usually included in the tube of the corolla, terminating in blackish-violet anthers oblong, 1.5 mm. long.
  Ovary cylindrical and sub-pentagonal, 10 mm. long, at the apex finely pubescent, narrowed at the apex to a slender style, 3 - 3.5 cm. long, glabrous, rose colour, topped with a large glandular stigma, spread into a disk.
  Capsule linear, sub-pentagonal, narrowed at both ends and surmounted by the persistent style, inserted obliquely on the peduncle, finely puberulous-furfuraceus when young; when mature ligneous brown, furnished with five deep sulcae, 6 cm. long and 0.5 cm. diameter, containing very numerous fine seeds, pale, elliptic-elongate, 0.8 by 0.25 mm., terminating at each end by a long pointed tail, at one end measuring 2 mm., at the other 4 mm. in length.

South Annam: Honba Mountains, 1200 - 1500 m. altitude, growing as an epiphyte in the forks of trees and in humus covering granite rocks in the shade of forest edges. Flowering on Sept.15, 1918.
  Observations: a magnificent ornamental plant, remarkable for the beauty of its flowers. The specific name which we have given on this occasion is for the beauty of the flowers which we observed at a time when things were improving in the war for France.
   The young plants transplant easily and the plants grow easily from seed but much less in the mountains of the country. Dr. Yersin has already commenced to cultivate this plant in the garden at Honba.
   Apparently a member of the R. cinnabarinum Hook, group from Sikkim but distinguished by the leaves and the many large flowers.
  Translated from the original French, J.S. Womersley, July 1985.
  Not in cultivation outside Vietnam.
   To my knowledge, the species R. triumphans has not been introduced into cultivation outside of Vietnam. It should not be confused with the Veitch hybrid which is widely grown. The hybrid 'Triumphans' was raised by the nursery firm Messrs. Veitch and Sons and is mentioned in the article "Hybrid Rhododendrons" by the Rev. Prof. Henslow in the Journal of The Royal Horticultural Society, August 1891, page 270. The hybrid was bred from 'Duchess of Edinburgh' (scarlet crimson in colour) crossed with the orange coloured species R. javanicum. 'Duchess of Edinburgh' was bred from R. lobbii (now named R. longiflorum) crossed with R. brookeanum (now R. javanicum var. brookeanum). From the reciprocal cross, R. javanicum crossed with 'Duchess of Edinburgh' was produced the Veitch hybrid 'Ne Plus Ultra'. The hybrid, 'Triumphans' has scarlet-crimson flowers but with larger tubes and smaller corolla lobes than the species R. triumphans. There is no difference of importance between it and 'Ne Plus Ultra' beyond slight shading in colour.

R. 'Triumphans'
R. 'Triumphans'
Photo by R. M. Withers

Subsection MALAYOVIREYA
  10. R. malayanum var. malayanum, Jack, Mai. Misc. , 2 [7] 1822, p. 17, has twice been collected in Thailand just north of the border with Malaya at Gunong Ina, Betong, district Pattani. Otherwise it is widespread in the Malay Peninsula, Sumatra, Borneo, Sarawak. Sabah and Celebes.
        This variety of the species is fully described in Dr. H. Sleumer's book, An Account of Rhododendron in Malesia, on page 532.
        The species, although not common, has been grown successfully in cultivation in Australia for a number of years by several growers of Vireyas. It was introduced into cultivation from Perdah by Dr. Peter Valder in January 1972, and by Professor K. Arisumi in January 1980 from Mt. Brinchang, Malaya. It has not been hybridised with other species.

R. malayanum
R. malayanum
Photo by Dr. John Rouse

Subsection EUVIREYA Series JAVANICA
  11. R. lochiae, F. Muel., Vict. Nat. 3 (1887) p. 157, well known to all members of the Australian Rhododendron Society, also is found outside the Malesian area, but to the south.
  Type: Sayer and Davidson. Mt. Bellenden Ker Summit, 1525 m., also from Mt. Bartle Frere, Mt. Spurgeon, Thornton Peak, Mt. Finnegan and other mountains in northeast Queensland.
        It is my belief, and was also the belief of the late Dr. Len Brass and others, that other Vireya species apart from R. lochiae, and yet to be discovered, exist in the mountains of North Queensland.
        In his book, An Account of Rhododendron in Malesia, Dr. H. Sleummer has a map on page 475 showing the distribution of Vireya rhododendrons in Malesia. He only lists 3 Vireya species as growing outside the Malesian area, 2 in Vietnam, R. triumphans and R. chevalieri, and 1 in Australia, R. lochiae.
        Little is known of the original introduction of the only known Australian species into cultivation. Apparently it was first grown by Hodgins, a Victorian nurseryman about 35 to 40 years ago. In 1951 the late Mr. I. Hammet reported that he had a plant "growing freely in ordinary loamy soil surrounded on all sides by rocks and overshadowed by trees". The late Mr. B. Menelaus collected seed of R. lochiae on Mt. Bartie Frere in North Queensland, in the early 1960's. It has since been collected by Mr. Donald Teese, and by a group of members of the Australian Rhododendron Society in the 1970's.
        R. lochiae is now widely grown, and has successfully crossed with a wide range of Vireya species in subsections Phaeovireya and Euvireya.

BIBLIOGRAPHY
Australian Rhododendron Society The Rhododendron
Henslow, Professor Journal of the Royal Horticultural Society, August 1891.
Jack, Malayan Miscellanies, Sumatran Mission Press, Bencoolen, Indonesia, 1822.
Journal College Science University, Tokyo, 30 (1)171, 1911.
Journal Bombay National History Society, Volume 65.
Kew Bulletin, 1910.
Rhododendrons d'Indochine.
Rhododendrons Sikkim Himal, Part 2.
Revue de Botanique Appliquee et d' Agriculture Troptcale IX annee. - Bulletin No. 92, April 1929.
Sleumer, Dr. H. Blumea, 1958 Suppl. 4, 47.
Sleumer, Dr. H. An Account of Rhododendron in Malesia.
The Rhododendron Association, The Species of Rhododendron, 1930.
The Royal Horticultural Society, Rhododendron and Camellia Year Book, 1968.
Victorian Naturalist, 3 (1887).


Volume 41, Number 3
Summer 1987

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