Tag:

Sikkim

Flowers of Sikkim — 350 species from the Sikkim Himalaya in northeast India, a compact yet botanically extraordinary region that climbs from subtropical valleys to the alpine zone beneath Kangchenjunga. Sikkim is a classic centre of Himalayan plant diversity, celebrated for its rhododendrons, primulas, orchids and gentians. Each entry provides a botanical description, distribution, habitat and flowering season with the original field photograph.

Ericaceae

Rhododendron glaucophyllum

by GP Jürgens

Rehder

Sikkim2004 392 P672
Sikkim (India), Lachung 3100 m
Sikkim2004 386 P664
Sikkim (India), Lachung 3100 m, May

Description

Rhododendron glaucophyllum is an Eastern Himalayan shrub distributed across Sikkim and adjacent India, Nepal, Bhutan and parts of south-western China and Myanmar. Its 172 GBIF records concentrate in this native range, the British, Canadian, New Zealand and United States points reflecting its long cultivation as an ornamental rhododendron. It grows in subalpine and alpine shrubberies, on open rocky slopes, cliffs, forest margins and moist banks, typically between about 2700 and 3700 m. The plant photographed at Lachung in Sikkim at 3100 m in May illustrates the species flowering in late spring within the cool, humid montane belt of the Eastern Himalaya.

It is a small, aromatic, evergreen shrub with peeling, papery bark and elliptic to oblong leaves that are dark green above and conspicuously glaucous and densely scaly (lepidote) beneath, the source of the epithet glaucophyllum. The flowers are borne in small terminal trusses; the campanulate corolla is pink to rose, sometimes paler or white, with the calyx well-developed and lobed, a distinctive feature of the species. Ten stamens and a lepidote ovary are typical of its subgenus. The fruit is a small, scaly, dehiscent capsule releasing numerous tiny seeds.

The species belongs to Rhododendron subgenus Rhododendron, section Rhododendron (the lepidote, scaly-leaved rhododendrons), and within it to the glaucophyllum group, characterised by aromatic foliage and a prominent calyx. Several varieties have been recognised across its range. Widely distributed and locally common, and well established in cultivation, R. glaucophyllum is not considered threatened, forming an attractive element of Eastern Himalayan subalpine scrub.

Author: Rehder · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, The Rhododendron Handbook (RHS)

Ericaceae

Rhododendron grande

by GP Jürgens

Wight

Nepal1992 196 P285 ergebnis
Nepal Suketar 2400m March 
Nepal1992 197 P286 ergebnis
Nepal Suketar 2400m March 

Description

Rhododendron grande is a tree species of the eastern Himalayan temperate forest belt, ranging through Nepal, Sikkim and Darjeeling in India, Bhutan, northern Myanmar and southwestern China (Yunnan, Tibet), with cultivated and naturalised records extending to Great Britain, Belgium, Canada and the United States; the GBIF dataset comprises some 284 georeferenced occurrences. It typically grows between 2000 and 3000 m in cool, humid broad-leaved and conifer forests, ravine margins and on shaded slopes, often forming an understorey component beneath Tsuga and Quercus. The photographed plant from Suketar in eastern Nepal at 2400 m, flowering in March, is characteristic of these mid-montane mist forests where high rainfall and persistent cloud cover prevail.

It is an evergreen shrub or small tree reaching 10–15 m, with stout branchlets and smooth grey-brown bark. The leaves are large, coriaceous, oblong-elliptic to oblanceolate, 15–30 cm long, dark glossy green above and conspicuously silvery to fawn lanate-tomentose beneath with a thin plastered indumentum. The inflorescence is a dense compact truss of 15–25 flowers; the corolla is campanulate, 4–5 cm long, ivory-white to creamy with a basal crimson-purple blotch, eight-lobed, and subtended by a swollen nectary. Stamens are 16, the ovary tomentose, and the fruit a woody curved capsule dehiscing to release numerous minute winged seeds.

Rhododendron grande belongs to subgenus Hymenanthes, subsection Grandia, a group of large-leaved species centred on the Sino-Himalaya and noted for their bicoloured indumentum. As one of the earliest-flowering large rhododendrons it is valued in horticulture and draws nectar-feeding birds and bumblebees. Though not globally threatened, populations face pressure from forest clearance and grazing.

Author: Wight · Sources: POWO (Kew), GBIF, Flora of China Vol. 14, Flora of Bhutan Vol. 2, Flora of Nepal, The Genus Rhododendron (Cox & Cox)

Ericaceae

Rhododendron griffithianum

by GP Jürgens

Wight

Bhutan2014 458
Yatong-La 3200m, May
Bh2008 150 P248
Yatong-La 3200m, May
Bh2008 151 P249
Yatong-La 3200m, May
Nepal 1994 254 ergebnis
Ost-Nepal Milka-Danda 2800m May 

Description

Rhododendron griffithianum is an eastern Himalayan species centred on India (Sikkim, Arunachal), Bhutan, Nepal and adjacent China, with about 219 georeferenced records; further occurrences in Britain, the Netherlands, Canada, the United States and New Zealand reflect its long cultivation as a horticultural ornamental and parent of hybrids. It grows in cool, humid temperate forest, on shaded ridges and ravine sides, often as an understorey or forest-margin shrub between roughly 2500 and 3300 m. The photographed plants from Yatong-La at 3200 m and the East Nepal Milke Danda at 2800 m, flowering in May, typify this moist mid-montane belt.

It is a large evergreen shrub to small tree with smooth, peeling, reddish-brown bark. The leaves are elliptic-oblong, leathery, glabrous and somewhat glaucous beneath, with a rounded base and prominent midrib. The inflorescence is a lax truss of few large flowers; the corolla is broadly campanulate, white sometimes flushed pink, faintly fragrant, and among the largest of any Himalayan rhododendron, with a calyx that is unusually well developed and lobed. The fruit is an elongate, ribbed, dehiscent capsule releasing numerous minute winged seeds.

Classified in subgenus Hymenanthes, R. griffithianum has been horticulturally pivotal, contributing its size and corolla form to many hardy garden hybrids. In the wild it occupies a narrow, oceanic-monsoon climatic band, and its dependence on undisturbed humid forest renders it sensitive to logging, grazing and warming, of biogeographic interest as an indicator of the wet eastern Himalayan forest flora.

Author: Wight · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, The Genus Rhododendron (Royal Botanic Garden Edinburgh)

Ericaceae

Rhododendron hodgsonii

by GP Jürgens

Hook. f.

Bhutan2014 502
Bhutan Yatong-La 3250m, May
Bhutan2014 508
Bhutan Yatong-La 3250m, May
Bh2008 129 G216
Bhutan Pele-La, 3000m April
Bh2008 594 G889
Bhutan Chele-La 3900m April
Nepal 1994 209 ergebnis
Ost-Nepal Mewa-Khola 2500m April 

Description

Rhododendron hodgsonii is a large evergreen shrub or small tree of the temperate and subalpine zones of the eastern Himalaya, native to India (Sikkim, Arunachal), Nepal, Bhutan and adjacent China, with over 440 georeferenced records (many of the further-flung being cultivated specimens in botanic gardens). It forms a conspicuous component of the upper broad-leaved and conifer-Rhododendron forests, typically between about 2500 and 3700 m. The photographed plants span this range in Bhutan, from Pele-La and Chele-La to Yatong-La at 3000-3900 m, and in eastern Nepal at Mewa-Khola at 2500 m, flowering from April into May as the snow recedes from the high passes.

The species is distinguished by its smooth, fawn to plum-coloured peeling bark and very large, leathery, obovate-elliptic leaves up to 30 cm long, dark glossy green above and clothed beneath with a thin, silvery to fawn, plastered indumentum. The flowers are borne in dense, rounded terminal trusses of fifteen to twenty-five blooms; the corolla is fleshy, campanulate and eight- to ten-lobed, ranging from magenta-rose to pale pink with darker nectar pouches at the base. The stamens are numerous and the stout style ends in a broad capitate stigma. The fruit is a stout, curved, woody capsule.

Rhododendron hodgsonii belongs to subgenus Hymenanthes, subsection Falconera, allied to R. falconeri but separable by its thinner leaf indumentum and rich magenta corolla. Named for Brian Houghton Hodgson, it is a keystone of the Himalayan Rhododendron forests, its leaves traditionally used for wrapping and its thickets providing shelter for montane wildlife. Locally abundant and not threatened, it is widely grown in temperate gardens.

Author: Hook. f. · Sources: POWO (Kew), GBIF, Flora of Bhutan, The Genus Rhododendron (Royal Botanic Garden Edinburgh), Rhododendrons of Sikkim-Himalaya (Hooker)

Ericaceae

Rhododendron keysii

by G & P Jürgens

Nutt.

Bhutan2014 529
Bhutan Pele-La 2900m, May
Bhutan2014 643
Bhutan Pele-La 2900m, May
BhutanPG2011 262011 Bhutan Rhod. keysii scaled
Bhutan Pele-La, 2800m June

Description

Rhododendron keysii is an eastern Himalayan shrub native to Bhutan, India (Arunachal Pradesh, Sikkim) and southern Tibet (China), with 202 georeferenced occurrences; further records from Canada, Great Britain and New Zealand reflect its cultivation as a curiosity in temperate gardens rather than a natural range. It grows in cool, humid montane and temperate forest, in scrub, forest margins and as an epiphyte or terrestrial shrub among conifers and broad-leaved trees, generally between about 2400 and 3300 m. It was photographed at the Pele-La pass in Bhutan at 2800 to 2900 m in May and June, within the moist mid-montane belt where mist and high rainfall favour its growth.

It is an erect, sparsely branched evergreen shrub 1 to 3 m tall, with scaly young shoots and rather thin, elliptic-lanceolate leaves that are lepidote beneath. The flowers are highly distinctive among rhododendrons: borne in small axillary clusters along the upper stems, they are narrowly tubular to cylindrical, only slightly flared at the mouth, and bicoloured, with an orange-red to brick-red tube and contrasting yellow-green lobes. The corolla shape recalls a Correa or a small Cestrum rather than a typical rhododendron. The fruit is a slender scaly capsule.

The species belongs to Rhododendron subgenus Rhododendron, section Rhododendron (subsection Cinnabarina, the keysii alliance), and its tubular axillary flowers make it instantly recognisable. The narrow tube and exserted style point to pollination by sunbirds. Ecologically it is a component of mossy montane forest undergrowth. It is not regarded as threatened, though uncommon and locally distributed, and is valued horticulturally for its unusual floral form.

Author: Nutt. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, The Genus Rhododendron (Cullen & Chamberlain monograph)

Ericaceae

Rhododendron lanatum

by GP Jürgens

Hook. f.

Bhutan2014 374
Bhutan Tumcheng-La 3900m, May
Bhutan2014 375
Bhutan Tumcheng-La 3900m, May
Bh2008 252 P398
Bhutan Tumching-La, 3400m April
Bh2008 270 P424 scaled
Bhutan Tumching-La, 3700m April
Bh2008 271 P425 1
Bhutan Tumching-La, 3700m April

Description

Rhododendron lanatum is an East Himalayan species restricted to the eastern Himalaya, ranging from Sikkim and adjacent northern India through Bhutan to south-eastern Xizang and Yunnan in China, with peripheral records in Nepal; its roughly 180 georeferenced occurrences (IN, BT, CN, NP) reflect a comparatively narrow distribution, supplemented by garden records in Britain and Sweden. It is a component of the subalpine Rhododendron-Abies forest and shrubberies, growing on humus-rich, acidic slopes and rocky moraine between about 3000 and 4300 m. The plants documented on the Bhutanese passes of Tumching-La and Tumcheng-La between 3400 and 3900 m, flowering from April into May, occupy exactly this cool, cloud-soaked subalpine zone.

It is an evergreen shrub or small tree to 3-4 m, conspicuous for the dense rusty to fawn woolly (lanate) indumentum that clothes the young shoots, leaf undersides and bud scales. The leaves are coriaceous, oblong-elliptic, glabrous and dark green above but covered beneath with a thick, two-layered tomentum of branched hairs. The bell-shaped (campanulate) flowers, pale to sulphur-yellow and often flecked with crimson at the base, are 3-4 cm long and grouped in dense terminal trusses of up to a dozen; the corolla bears five lobes, ten stamens and a glabrous ovary. The fruit is a curved, woody, septicidal capsule releasing numerous minute winged seeds.

Rhododendron lanatum belongs to subsection Lanata of subgenus Hymenanthes, a small group defined by their woolly indumentum and yellow campanulate flowers, allied to R. wightii. Its narrow eastern Himalayan range and dependence on intact subalpine forest make it locally vulnerable to grazing, fire and woodland degradation, though it remains frequent within Bhutan's protected highlands.

Author: Hook. f. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Cox's The Larger Rhododendron Species, The Genus Rhododendron (Royal Botanic Garden Edinburgh)

Ericaceae

Rhododendron lepidotum

by GP Jürgens

Hook.f.

Nepal 95 386 P685 ergebnis
Nepal Bahanjyang 3800m October
Nepal 95 424 P738 ergebnis
Nepal Bahanjyang 3800m October
BhutanPG2011 629 01
Bhutan Ludlow-Sherriff-Trail Ken-La, 4300m July
BhutanPG2011 620 scaled
Bhutan Ludlow-Sherriff-Trail Ken-La, 4300m July
Nepal 99 548 ergebnis
West-Nepal Churta-Khola, 3800m June
Sikkim2011 183
Sikkim Lachung 2650m, June
Ericaceae

Rhododendron leptocarpum

by GP Jürgens

Nutt.

Sikkim2004 436 P760
Sikkim/India Lachung 3600m May
Sikkim2004 437 P761
Sikkim/India Lachung 3600m May

Description

Rhododendron leptocarpum is an Eastern Himalayan endemic restricted to the moist temperate and subalpine belt of Sikkim, Bhutan, adjacent India, southern Tibet (China) and northern Myanmar, where GBIF documents some 119 georeferenced collections across the four countries CN, IN, MM and BT. It is an epiphytic or terrestrial shrub of mossy fir and Rhododendron forest, frequently perching on trunks, boulders and humus-laden ledges in a cool, perhumid, fog-bathed climate. The photographed plant at Lachung in northern Sikkim, growing near 3600 m and flowering in May, is typical of its altitudinal range of roughly 2700-4000 m.

The species is a small, twiggy shrub, often pendulous or scandent when epiphytic, with thin, flaky bark and slender, scaly young shoots. The leaves are evergreen, coriaceous, elliptic to oblong-lanceolate, glossy above and densely lepidote beneath, the scales golden to ferruginous. The campanulate to broadly funnelform corolla is comparatively small, pale to deep yellow, sometimes flushed greenish, borne in few-flowered terminal umbels; the stamens are 10 and the slender style is sharply deflexed. The diagnostic fruit is an elongate, narrowly cylindrical, curved capsule, the slenderness of which gives the epithet leptocarpum ('slender-fruited').

Placed in Rhododendron subgenus Rhododendron, the lepidote (scaly-leaved) rhododendrons, R. leptocarpum belongs to a group of small-flowered yellow species centred on the wettest Eastern Himalayan ranges. Its epiphytic habit and narrow elevational and geographic span make it a sensitive indicator of intact, high-humidity cloud forest, a habitat increasingly fragmented by grazing, fuelwood collection and warming-driven upslope shifts of the forest belt.

Author: Nutt. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, The Rhododendron Handbook (Royal Horticultural Society), Cox & Cox A Encyclopedia of Rhododendron Species

Ericaceae

Rhododendron lindleyi

by GP Jürgens

T. Moore

Bhutan2014 311
Bhutan Jakar 2400m, May
Bhutan2014 448
Bhutan Jakar 2400m, May
Sikkim2004 56 G98
Sikkim West-Bengal, Bersay 2810m April
Nepal 1994 257 ergebnis
Ost-Nepal Milka-Danda 2850m April 
Nepal 1994 263 ergebnis
Ost-Nepal Milka-Danda 2850m May 

Description

Rhododendron lindleyi is an epiphytic to terrestrial rhododendron of the eastern Himalaya, recorded in GBIF from India, Nepal, Bhutan, China and Myanmar across 154 occurrences. It is characteristic of cool, humid mid-montane broad-leaved and conifer forest, growing as an epiphyte on mossy trunks or on cliffs and steep banks between roughly 2200 and 3000 m. Collections cited from the image span Jakar in Bhutan at 2400 m in May, Bersay in the Sikkim-West Bengal borderlands at 2810 m in April, and Milka-Danda in east Nepal at 2850 m in April-May, indicating a spring-flowering species of the perhumid forest belt.

It is a straggling, sparsely branched shrub 1-3 m tall with smooth, peeling reddish-brown bark and rather thin, scaly branchlets. The leaves are elliptic-oblong, leathery, glaucous and densely lepidote (scaly) beneath. The inflorescence is a loose terminal truss of 3-6 large, fragrant flowers; the corolla is broadly funnel-campanulate, 7-10 cm long, white often flushed with pink and marked with a yellow basal blotch, the tube exterior bearing scattered scales. There are usually ten stamens, an elongate scaly style, and the fruit is a slender, scaly, septicidal capsule releasing numerous minute winged seeds adapted to epiphytic establishment.

The species belongs to Rhododendron subgenus Rhododendron section Maddenia, the lepidote, often epiphytic, large-flowered rhododendrons. Named for the botanist John Lindley, it is prized in horticulture for its scented bloom. Pollination is by long-tongued insects, with dust-seed dispersal favouring colonisation of bark and rock. Though locally frequent, its dependence on undisturbed humid forest leaves it sensitive to habitat clearance.

Author: T. Moore · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, The Genus Rhododendron (Edinburgh Revision)

Ericaceae

Rhododendron maddenii

by G & P Jürgens

Hook. f.

Sikkim2011 171
Sikkim Lachen 2760m, June
61F33B91D6814425A5DC452DD80DA368
Bhutan Paro, 2400m June

Description

Rhododendron maddenii is a temperate Himalayan and Indo-Burmese species native from India and Bhutan through China to Myanmar and Vietnam; GBIF's 432 records also reflect its wide cultivation, with occurrences logged from New Zealand, Australia, Britain, Japan, Korea, Malaysia and the United States. In the wild it grows on steep, often rocky and humus-rich slopes, cliff ledges and the margins of temperate broadleaf and conifer forest, frequently as an epiphyte or lithophyte. The figured plants from Lachen in Sikkim at 2760 m and Paro in western Bhutan at 2400 m, both flowering in June, place it firmly within the cool temperate forest belt where summer monsoon moisture and high atmospheric humidity prevail.

It is an evergreen shrub or small tree, the bark smooth and peeling in papery flakes. The leaves are leathery, elliptic to oblong-lanceolate, dark green and glabrous above, the undersurface densely covered with brown lepidote scales characteristic of the subgenus. The flowers, borne in terminal trusses of few blooms, are large, funnel-form to tubular-campanular and strongly fragrant, white often flushed with pink and scaly on the outside of the corolla tube. There are typically numerous stamens and a long style, the ovary lepidote. The fruit is an elongate, scaly, dehiscent capsule releasing many small seeds adapted to wind and epiphytic establishment.

Within Rhododendron subgenus Rhododendron, R. maddenii belongs to the large, taxonomically complex subsection Maddenia, distinguished by lepidote foliage and showy scented corollas, and it shows considerable variation in size and indumentum across its range. The fragrant, pale flowers attract long-tongued moths and other nocturnal pollinators. Long prized in horticulture, it is the source of many hybrids; in the wild it remains generally secure, though habitat loss and over-collection threaten some local populations.

Author: Hook. f. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, The Genus Rhododendron (Royal Horticultural Society), Cullen's revision of lepidote Rhododendron