Tag:

Spring

Thymelaeaceae

Daphne sureil

by GP Jürgens

W.W.Sm. & Cave

Bhutan2012 638
Bhutan Tserang, 1600m September
Bhutan2015 218
Bhutan Zhemgang 1000m, October
Bh2008 515 P790
Bhutan Chongsakha, 1800m April

Description

Daphne sureil is a shrub of the eastern Himalaya and adjacent Southeast Asia, recorded from India, Thailand, Nepal, Bhutan, Myanmar, Bangladesh and Vietnam, with about 124 documented occurrences. It is a plant of warm-temperate and subtropical broad-leaved forest, growing in the understorey and along forest margins, ravines and stream banks on moist, well-drained slopes. In Bhutan it occupies the lower to middle montane belt across a broad elevational span, as shown by collections from Tserang at about 1600 m in September, Zhemgang at 1000 m in October and Chongsakha at 1800 m in April, the spring date corresponding to its flowering period.

The species is an evergreen shrub with slender, glabrous branches bearing alternate, shortly petiolate leaves that are elliptic to oblanceolate, entire, acuminate or acute at the apex and tapering at the base, leathery and glossy above with a paler lower surface. The flowers are borne in small terminal clusters and lack petals, the floral display formed instead by a tubular, fragrant white to creamy perianth of four spreading lobes, the tube silky-pubescent without and enclosing eight stamens in two whorls. The fruit is a fleshy ovoid drupe, ripening red, containing a single seed.

Daphne sureil was described by W. W. Smith and Cave from the eastern Himalaya and belongs to the predominantly evergreen Asian assemblage of the genus. As in other Daphne species, the bark contains tough phloem fibres and the tissues bear the diterpenoid daphnane compounds responsible for their acridity and toxicity. The bird-dispersed drupes and strongly scented, presumably moth-pollinated flowers reflect typical thymelaeaceous biology. The species is locally frequent in suitable forest but, being tied to lower-montane broad-leaved woodland, is potentially vulnerable to habitat clearance at its lower elevational limits.

Author: W.W.Sm. & Cave · Sources: POWO (Kew), GBIF, Flora of Bhutan Vol. 1, Flora of China Vol. 13, Flora of Nepal, Halda monograph The Genus Daphne

Thymelaeaceae

Daphne tangutica

by G & P Jürgens

Maxim.

Sikkim 2006 380 ergebnis
Sikkim 2006 379 ergebnis
India West-Bengal, Tamrong 3200m, May
BhutanPG2011 486 scaled
Bhutan Ludlow-Sherriff-Trail Warrtlang-La, 4350m June

Description

Daphne tangutica is distributed across a broad elevational and geographical range from the eastern Himalayas to central and western China, with the core of its distribution in Sichuan, Gansu, and Qinghai provinces. GBIF records over 1,150 occurrences, predominantly from China, with additional records from Bhutan, India, Nepal, and Pakistan. The species inhabits Rhododendron scrub, alpine meadows, rocky slopes, and open coniferous forest margins at 2,500–4,500 m elevation. Collections from Tamrong in West Bengal at 3,200 m and from the Warrtlang-La along the Ludlow–Sherriff Trail in Bhutan at 4,350 m demonstrate its remarkable altitudinal amplitude within the eastern Himalayan region.
Daphne tangutica is an evergreen shrub, typically 0.5–1.5 m tall, compact and densely branched. Leaves are alternate, clustered towards the branch tips, oblanceolate to elliptic, 3–8 cm long, coriaceous, dark glossy green above and paler beneath, with entire revolute margins. Flowers are borne in dense terminal clusters of 3–8, each flower with a tubular hypanthium 10–14 mm long, the four spreading lobes white internally and purplish-rose externally. The flowers are intensely fragrant. Stamens are eight, in two whorls, inserted on the hypanthium tube. The fruit is an ovoid drupe, 6–8 mm long, red at maturity, containing a single seed.
Daphne tangutica was described by Maximowicz in 1882 from material collected in Gansu. It is closely related to D. retusa, and the two species have been confused in herbaria; D. tangutica is generally distinguished by its longer, more lanceolate leaves and more elongate hypanthium tube. The occurrence at 4,350 m on the Warrtlang-La approaches the upper limit for any Daphne species in the Himalayas and attests to the species' tolerance of extreme alpine conditions. It has been widely introduced into horticulture in Europe and North America, prized for its fragrant spring flowers and compact evergreen habit.

Author: Maxim. · Sources: POWO (Kew), GBIF, Flora of China Vol. 13, Flora of Bhutan Vol. 2, Brickell & Mathew: Daphne — The Genus in the Wild and in Cultivation (1976)

Lardizabalaceae

Decaisnea insignis

by G & P Jürgens

Hook.f. & Thomson

Sikkim 2006 329 ergebnis
India West-Bengal, Chaana 1700m, May

Description

Decaisnea insignis is a deciduous shrub of the Himalaya and southwest China, native to China, India, Bhutan, Nepal and Myanmar, and now widely grown as an ornamental, accounting for numerous records in Europe, North America and elsewhere. It occupies moist temperate forest, forest margins, ravines and shrubby slopes, typically between about 1500 and 3500 m. The photographed plant from Chaana in West Bengal, India, at roughly 1700 m and flowering in May, is characteristic of cool, humid mid-montane forest where it favours sheltered, well-watered situations with rich, humus-laden soils.

The plant is an erect, sparsely branched shrub with stout, pithy stems. The leaves are large, alternate, imparipinnate, with numerous ovate to ovate-lanceolate, entire, acuminate, glaucous-backed leaflets. The flowers are borne in pendulous terminal panicles and are functionally unisexual, with six narrow, greenish-yellow, petaloid sepals and no true petals. The most distinctive feature is the fruit: pendent, cylindrical, sausage-shaped follicles that ripen a striking metallic blue, the fleshy interior containing a translucent, sweetish pulp embedding numerous flattened black seeds, giving rise to the common name dead man's fingers.

The genus commemorates the French botanist Joseph Decaisne, and insignis alludes to its remarkable blue fruit. Some authors treat the blue-fruited Himalayan plants as D. insignis distinct from the yellow-fruited Chinese D. fargesii, though the two are frequently united. The Lardizabalaceae is a small, mainly East Asian family of climbers and shrubs; D. insignis is anomalous as an erect, non-twining member. The conspicuous fleshy fruits suggest vertebrate dispersal, and the species is widely cultivated and not threatened.

Author: Hook.f. & Thomson · Sources: POWO (Kew), GBIF, Flora of China Vol. 7, Flora of Bhutan Vol. 1, Flora of Nepal, A Revision of the Lardizabalaceae

Fabaceae

Delonix regia

by GP Jürgens

(Bojer ex. Hook.) Raf.

Nepal 97 595 P1150
Nepal Sabha-Khola 1200m,May
Nepal 97 596 G1151
Nepal Sabha-Khola 1200m,May
Nepal 1994 335 2 ergebnis
Ost-Nepal Chainpur 400m May 

Description

Delonix regia is one of the most widely cultivated ornamental trees of the tropics, native to the deciduous and dry forests of western Madagascar but now naturalised and planted across the warm regions of every continent. GBIF records reflect this pantropical spread, with occurrences across India, Australia, Brazil, Mexico, the United States, Tanzania, Madagascar, Thailand, China, Kenya, South Africa and the Dominican Republic, drawn from more than 27,000 documented collections. In the eastern Himalaya it occurs only as an introduced shade and avenue tree of the warm lowlands and foothills; the photographed material from the Sabha-Khola valley at 1200 m and from Chainpur in East Nepal at around 400 m, flowering in May, lies near the upper altitudinal limit at which the species thrives, requiring frost-free, seasonally dry, sun-exposed sites.

It forms a spreading, umbrella-crowned deciduous tree to 10–15 m, the trunk often buttressed and the bark smooth and grey. The leaves are large, bipinnate and fern-like, with 10–25 pairs of pinnae each bearing numerous small oblong leaflets. The flowers, borne in showy corymbose racemes, are large and zygomorphic with five clawed, spreading petals, four scarlet to orange-red and one larger, whitish or yellow petal streaked with red; the ten stamens are long and exserted with red filaments. The fruit is a large, woody, flattened legume to 60 cm long, persistent and dark brown when ripe, containing numerous hard, mottled seeds.

A member of the Caesalpinioid clade of the Fabaceae, Delonix is a small genus centred on Madagascar and East Africa. Though abundant in cultivation, the species is assessed as of conservation concern in its native range owing to deforestation and a highly restricted wild distribution. Its conspicuous flowering, drought tolerance and nitrogen-fixing capacity have made it a favoured street and amenity tree throughout the tropics, where it is valued equally for shade and ornament.

Author: (Bojer ex. Hook.) Raf. · Sources: POWO (Kew), GBIF, Flora of Nepal, Flora of Madagascar (Flore de Madagascar et des Comores), Legumes of the World (Lewis et al.)

Orchideaceae

Dendrobium amoenum

by G & P Jürgens

Wall. ex Lindl.

Nepal 2009 114 ergebnis
Nepal Helambu Indrawati-Valley 1500, May

Description

Dendrobium amoenum Wall. ex Lindl. is an epiphytic orchid distributed across the central and eastern Himalaya and adjacent ranges, with records (GBIF: c. 147 occurrences) from India, Nepal, Bhutan and Myanmar, extending into the Malesian region (Indonesia). It is a characteristic element of humid temperate and subtropical broad-leaved forests, growing on mossy trunks and branches at roughly 1,000–2,000 m. The photographed material from Nepal's Helambu region in the Indrawati Valley, at about 1,500 m and flowering in May, falls squarely within its preferred mid-montane belt, where seasonal monsoon humidity and cloud-forest conditions favour epiphytic growth.

The species forms slender, pendulous, terete stems up to 30–60 cm long, often becoming leafless before flowering and bearing thin internodes. The leaves are distichous, lanceolate and deciduous, leaving conspicuous nodal sheaths. Flowers are borne singly or in small clusters from the nodes of older canes, are fragrant, and measure roughly 3–4 cm across. The sepals and petals are white, frequently tinged or tipped with pale rose-purple, while the rounded, pubescent lip is white with a yellow to greenish central disc and a fine purple apical margin. The column is short, bearing four pollinia within an operculate anther cap.

Dendrobium amoenum belongs to the large, taxonomically complex genus Dendrobium (section Dendrobium), members of which display the characteristic deciduous habit and nodal flowering. Like many Himalayan epiphytic orchids it is sensitive to deforestation and to collection pressure, and the genus is listed under CITES Appendix II. The input family "Orchideaceae" is an orthographic variant of the accepted Orchidaceae.

Author: Wall. ex Lindl. · Sources: POWO (Kew), Flora of Bhutan Vol. 3, Flora of Nepal, GBIF, Pearce & Cribb: The Orchids of Bhutan (2002)

Orchideaceae

Dendrobium aphyllum

by G & P Jürgens

C.E.C. Fisch.

Sikkim2011 17
Sikkim Lachen 2460m, June
Bhutan2014 703
Bhutan Wangdi Phodrang 2280m, May
BhutanPG2011 56 ergebnis
Bhutan Jakar, 20m June
Bhutan2014 702
Bhutan Jakar, 2600m June
Nepal 1994 8 ergebnis
Ost-Nepal Tumlingtar 340m April

Description

Dendrobium aphyllum is a widespread epiphytic orchid of tropical and subtropical Asia, ranging from India and Nepal through southern China and across mainland Southeast Asia, with GBIF documenting occurrences from India, China, Thailand, Bhutan, Nepal, Vietnam, Myanmar and Laos among many territories. It grows as an epiphyte, and sometimes a lithophyte, on tree trunks and rocks in warm, humid lowland and lower montane forest, enduring a distinct dry season during which the canes shed their leaves. It occupies low to middle elevations; the records span Tumlingtar in eastern Nepal at about 340 m to Sikkim's Lachen and Bhutanese sites up to roughly 2600 m, with the photographed material flowering from April through June across this broad altitudinal range.

The plant produces long, slender, pendulous cane-like stems that branch and trail from the host, leafy when young and largely leaf-shedding before flowering. The leaves are thin, lanceolate and deciduous. The flowers emerge in twos and threes from the nodes of the bare, hanging canes, fragrant and delicately coloured, with pale rose-pink to lilac sepals and petals. The labellum is broadly funnel-shaped to subobicular, cream to pale yellow and finely downy within, often marked with darker veining and rolled around the column to form a trumpet, the lower margin sometimes faintly fringed. The fruit is a pendent capsule.

D. aphyllum is placed in Dendrobium section Dendrobium and is characterised by its leafless flowering canes, as reflected in the epithet; it has accumulated synonymy and is sometimes confused with related pendent species such as D. primulinum and D. anosmum. Long cultivated as an ornamental and used in some traditional medicines, it remains common over much of its vast range, though localised populations are depleted by wild collection and lowland forest clearance.

Author: C.E.C. Fisch. · Sources: POWO (Kew), GBIF, Flora of China, The Orchids of Bhutan (Pearce & Cribb), Dendrobium and its Allies (Lavarack et al.)

Orchideaceae

Dendrobium formosum 

by GP Jürgens

Roxb. ex Lindl.

Nepal 2001 507 ergebnis ergebnis
Nepal (Gorkha) Arkhet 720m, May
Nepal 2001 508 ergebnis ergebnis
Nepal (Gorkha) Arkhet 720m, May

Description

Dendrobium formosum is an epiphytic orchid of the eastern Himalaya and Indo-Burmese region, native to India, Nepal, Bhutan, Myanmar, Thailand and the Philippines; its roughly 88 georeferenced GBIF records also include cultivated material in Europe, the United States and Brazil, reflecting its horticultural popularity. In Nepal it occurs at low to mid elevations, as illustrated by the collection near Arkhet in Gorkha district at about 720 m in May, where it grows on trunks and branches in warm, humid subtropical broad-leaved forest, favouring shaded, mossy bark with high atmospheric humidity.

The species forms erect, cane-like pseudobulbous stems whose leaf sheaths, like the young growth, are clothed in conspicuous blackish-brown hairs, a feature of section Formosae. The leaves are distichous, oblong-lanceolate and leathery. Flowers are borne in short few-flowered racemes near the stem apex and are large and showy, with broad, pure white spreading sepals and petals and a trumpet-shaped labellum marked by a bright yellow or orange throat blotch. The fruit is a ribbed dehiscent capsule releasing dust-like seeds.

Within the vast genus Dendrobium, D. formosum anchors section Formosae, a group of black-haired species prized for their substantial white blooms. As a forest epiphyte dependent on intact canopies and mycorrhizal germination, it is vulnerable to deforestation and over-collection for the ornamental trade, and like all Orchidaceae is listed on CITES Appendix II regulating international commerce in wild-sourced plants.

Author: Roxb. ex Lindl. · Sources: POWO (Kew), GBIF, Flora of China Vol. 25, Flora of Bhutan Vol. 3, Flora of Nepal, The Genus Dendrobium (Lavarack, Harris & Stocker)

Orchideaceae

Dendrobium heterocarpum

by GP Jürgens

Wall. ex Lindl.

Nepal1992 94 P130 ergebnis
Nepal Amjilassa 2300m March 
Nepal1992 162 P239 2 ergebnis
Nepal Amjilassa 2300m March 
Nepal1992 163 P244 ergebnis
Nepal Amjilassa 2300m March 

Description

Dendrobium heterocarpum is a widespread epiphytic orchid of the tropical and subtropical forests of southern and southeastern Asia. GBIF data document its broad native range across the Philippines, Thailand, India, Nepal, Vietnam, China, Indonesia, Bhutan, Sri Lanka and Myanmar, with additional records from cultivation in the United States, Britain, Belgium and Germany, totalling around 261 occurrences. It grows as an epiphyte on the trunks and larger branches of trees in seasonally dry, well-lit montane and submontane forest, often in regions with a marked dry season that triggers flowering. The photographed plant from Amjilassa in eastern Nepal at 2300 m, flowering in March, illustrates its occurrence in the mid-elevation hill forests of the central Himalaya, where spring blooming follows the cool dry winter.

It is a sympodial epiphyte with clustered, erect to pendent, cane-like pseudobulbs that are somewhat fusiform and longitudinally furrowed when old, bearing several lanceolate, deciduous leaves along their length. The flowers, borne in small lateral clusters from nodes of leafless canes, are fragrant, with cream to pale yellow, often reflexed sepals and petals; the labellum is broad and recurved, golden-yellow with reddish-brown longitudinal veining and a pubescent disc. The fruit is a ribbed, ellipsoid capsule releasing dust-like seeds.

Dendrobium is among the largest orchid genera, and D. heterocarpum belongs to section Dendrobium, characterised by deciduous-leaved, nodally flowering canes. Long valued in horticulture for its sweetly scented, durable flowers, the species is collected from the wild across parts of its range, and like most epiphytic orchids it is listed under CITES Appendix II to regulate international trade. Its pollination depends on deceptive attraction of bees to the showy, nectarless labellum.

Author: Wall. ex Lindl. · Sources: POWO (Kew), GBIF, Flora of Nepal, Flora of China (Orchidaceae), The Genus Dendrobium (Lavarack, Harris & Stocker)

Orchideaceae

Dendrobium jenkinsii

by GP Jürgens

Wall. ex Lindl.

Bhutan2014 716
Bhutan Wangdi Phodrang 2280m, June
Bh2008 454 P712
Bhutan Tsang-Chu, 1520m April

Description

Dendrobium jenkinsii is a small epiphytic orchid distributed across the Eastern Himalaya, southern China and mainland Southeast Asia, with GBIF occurrences from China, Bhutan, India, Vietnam, Myanmar, Laos and Thailand among others. It grows as an epiphyte on tree trunks and large branches in open, well-lit montane and submontane forest, often on exposed boughs where it endures a marked seasonal alternation of monsoon moisture and a dry, cool resting period. It occurs at low to middle elevations; the Bhutanese records from Wangdue Phodrang at about 2280 m in June and from the Tsang-Chu valley at 1520 m in April bracket its altitudinal range and indicate spring to early-summer flowering.

The species forms small, clustered, ovoid to discoid pseudobulbs pressed against the substrate, each compressed, wrinkled when mature and bearing a single leathery apical leaf. The inflorescence is short and few-flowered, arising near the pseudobulb apex. The flowers are comparatively large for the plant's size and bright golden-yellow, with spreading, broadly elliptic sepals and petals. The labellum is the showiest part, broad, orbicular-reniform and conspicuously fringed or fimbriate at the margin, with a densely hairy or velvety disc; the short column bears a foot forming a mentum with the lateral sepals. The fruit is a small capsule.

D. jenkinsii belongs to Dendrobium section Densiflora and is closely allied to the larger D. lindleyi (D. aggregatum), from which it differs chiefly in its solitary or few-flowered inflorescences and smaller stature; the two have at times been confused or treated as conspecific. The species is much sought in horticulture, and wild collection compounds the pressures of forest loss across its range, making it a taxon of potential conservation concern despite a wide overall distribution.

Author: Wall. ex Lindl. · Sources: POWO (Kew), GBIF, Flora of China, The Orchids of Bhutan (Pearce & Cribb), Dendrobium and its Allies (Lavarack et al.)

Orchideaceae

Dendrobium nobile

by GP Jürgens

Lindl.

Bhutan2014 170
Bhutan Trashiyangtse 2120m, May
Sikkim2004 441 G769
Sikkim/India Tista-Valley 2400m May
Sikkim2004 442 P770
Sikkim/India Tista-Valley 2400m May

Description

Dendrobium nobile is a widespread epiphytic orchid of the Himalaya and Indochina, native to China, India, Bhutan, Nepal, Myanmar, Vietnam and Laos, and now cultivated and naturalised far beyond, with records reported from many countries reflecting its enormous horticultural popularity. In the wild it grows as an epiphyte on mossy tree trunks and on shaded rocks in subtropical to warm-temperate broadleaved forest, chiefly between about 1000 and 2500 m. The plants documented here come from Trashiyangtse in eastern Bhutan at 2120 m and from the Tista Valley in Sikkim at 2400 m, both flowering in May at the close of the dry season.

The plant forms clustered, erect to pendulous, cane-like pseudobulbous stems that are fleshy, jointed and longitudinally grooved, bearing distichous, oblong-lanceolate leaves along their length; the leaves are usually deciduous before flowering. Inflorescences arise from the nodes of the leafless canes, each short raceme bearing one to three large, showy, fragrant flowers. The sepals and petals are white to rose-pink, deepening toward the tips, while the broad, rounded labellum is downy and conspicuously marked with a deep maroon-purple blotch in its throat ringed by paler margins. The column is short and the pollinia waxy; the fruit is an elongate dehiscent capsule releasing dust-like seeds.

As the nomenclatural type of section Dendrobium, this species is among the most important and intensively bred orchids in cultivation, with countless hybrids and named clones. Wild populations, however, have been heavily depleted by over-collection for horticulture and traditional medicine, and the species is listed on CITES Appendix II. Continued habitat loss across its native range makes in-situ conservation and sustainable trade regulation a significant concern.

Author: Lindl. · Sources: POWO (Kew), GBIF, Flora of China, The Orchids of Bhutan (Pearce & Cribb), Flora of Bhutan, CITES Appendices, Dendrobium monograph