Tag:

Autumn

Urticaceae

Boehmeria hamiltoniana

by GP Jürgens

Wedd.

Bhutan2012 693
Bhutan Galephu 900m, September

Description

Boehmeria hamiltoniana is a subtropical shrub or tall herb of the Himalayan foothills and adjacent Southeast Asia, recorded from India, China, Nepal, Thailand, Bhutan, Myanmar and Indonesia across some 115 GBIF occurrences. The illustrated plant was photographed at Galephu in southern Bhutan at about 900 m in September. It grows in warm, humid lowland and submontane settings, along forest margins, streamsides, ravines and disturbed ground generally below about 1500 m, favouring shaded, moist, fertile soils.

The plant is a perennial herb or soft-wooded shrub with erect, sometimes pubescent stems. The leaves are opposite or alternate, ovate to ovate-lanceolate, with a serrate or dentate margin and an acuminate apex, three-nerved from the base and often roughish or hairy. As in the Urticaceae the flowers are small, greenish and unisexual, lacking petals; they are densely aggregated into slender, often interrupted axillary spikes or panicles. The female flowers develop into small dry achenes enclosed in the persistent perianth, each containing a single seed.

Boehmeria belongs to the nettle family but, unlike true nettles, lacks stinging hairs. The genus includes the economically important ramie (Boehmeria nivea), valued for its strong bast fibres, and several Himalayan species are used locally for cordage. Wind plays a role in pollination of the inconspicuous flowers. B. hamiltoniana is widespread and ecologically tolerant of disturbance, and is therefore of least conservation concern, persisting readily along trails and forest edges.

Author: Wedd. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Flora of Nepal, Friis & Wilmot-Dear – Revision of Boehmeria (Urticaceae)

Urticaceae

Boehmeria penduliflora

by GP Jürgens

Wedd. ex D.G.Long

Bhutan2015 116
Bhutan Galephug 600m, October
Bhutan2015 117
Bhutan Galephug 600m, October

Description

Boehmeria penduliflora is a shrubby false-nettle distributed from the Himalaya and southern China through Indochina and Southeast Asia, with GBIF documenting nearly 2000 occurrences including naturalised records on Indian Ocean islands such as Reunion and Mauritius. It favours warm, humid lowland and submontane settings: streambanks, forest margins, roadside thickets and disturbed scrub on moist soils. The photographed plant grows in southern Bhutan at Gelephu around 600 m, in flower or fruit in October; the species is most frequent below about 1500 m in the subtropical foothill zone where it can form sizeable bushes.

The plant is a much-branched, erect to spreading shrub reaching two to three metres, with terete, finely pubescent young stems and, unlike true nettles, no stinging hairs. The leaves are opposite or subopposite, narrowly lanceolate to elliptic, long-acuminate, serrate-margined and three-nerved from the base, scabrid above and paler beneath. The minute unisexual flowers are densely clustered in glomerules arranged along slender, pendulous axillary spikes, a feature reflected in the epithet penduliflora. The fruit is a small ellipsoid achene enclosed in the persistent perianth.

Boehmeria belongs to the tribe Boehmerieae of the Urticaceae and includes the economically important ramie; B. penduliflora yields a usable bast fibre and is browsed by livestock, with leaves used as fodder and occasionally in traditional medicine. Its drooping inflorescences and lanceolate leaves readily distinguish it within the genus. Widespread, vigorous and tolerant of disturbance, it is of least concern and has naturalised well beyond its native Asian range as a hedge and fibre plant.

Author: Wedd. ex D.G.Long · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Boehmeria revision (Wilmot-Dear & Friis)

Urticaceae

Boehmeria virgata subsp. macrophylla

by GP Jürgens

(Hornem.) Friis & Wilmot-Dear

Bhutan2012 730
Bhutan Galephu 500m, October

Description

Boehmeria virgata subsp. macrophylla (Hornem.) Friis & Wilmot-Dear is a widespread paleotropical shrub of the nettle family, recorded by GBIF in over 2500 occurrences across an extraordinarily broad range that includes India (IN), Nepal (NP), China (CN), Thailand (TH) and Indonesia (ID), as well as much of tropical Africa (Tanzania, Cameroon, Gabon, Uganda, Angola), the Indian Ocean islands (Madagascar, Réunion, Mauritius, Comoros) and Australia (AU). It occupies forest margins, streambanks, clearings and disturbed secondary vegetation at low to mid elevations, and was photographed at Galephu in southern Bhutan at 500 m in October, in the warm subtropical foothills.

The plant is a shrub or coarse perennial herb with terete, often pubescent stems. The leaves are large, alternate or subopposite, broadly ovate to elliptic with a serrate margin, acuminate apex and three prominent basal veins, the lower surface frequently pale and softly hairy. As in all Boehmeria, the foliage lacks the stinging hairs found elsewhere in Urticaceae. The plant is monoecious, with minute unisexual flowers crowded into globose clusters arranged along slender, often elongate, interrupted spike-like inflorescences; female flowers have a tubular perianth enclosing a single ovule. The fruit is a small achene enclosed in the persistent, sometimes winged perianth.

This taxon belongs to a polymorphic complex that has been treated under various names including Boehmeria macrophylla, and the subspecific rank reflects Friis and Wilmot-Dear's revision integrating the Asian and African material. Wind pollination and the dust-like achenes account for its vast distribution. Stem fibres of Boehmeria species, notably ramie, are economically important, and the plant readily colonises disturbed ground, making it a frequent component of regenerating tropical and subtropical forest.

Author: (Hornem.) Friis & Wilmot-Dear · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Urticaceae revision (Friis & Wilmot-Dear)

Rutaceae

Boenninghausenia albiflora

by GP Jürgens

(Hook.) Meisn.

Bhutan2012 123
Bhutan Haar-Valley, 3100m September
Bhutan2012 125
Bhutan Haar-Valley, 3100m September

Description

Boenninghausenia albiflora is a delicate, aromatic herb of the Sino-Himalayan and East Asian region, recorded by GBIF from China, Japan, Taiwan, the Himalaya and Southeast Asia, with more than 5600 occurrences attesting to its frequency. It grows on shaded forest floors, mossy banks, rocky stream gullies and clearings in temperate and subtropical woodland, often on humus-rich or stony ground. The photographed population occurs in Bhutan in the Haa Valley at about 3100 m, flowering in September toward the end of the monsoon; the species ranges broadly from around 1000 to 3500 m across its Himalayan distribution.

The plant is a glabrous, gland-dotted perennial or subshrub with slender, much-branched stems woody only at the base, the whole exuding the citrus-rue scent characteristic of the family. The leaves are alternate and two- to three-pinnately compound, the small ultimate leaflets obovate to oblong, thin, glaucous beneath and conspicuously pellucid-punctate. Numerous small white to cream flowers are borne in lax terminal panicles, each with four petals, eight long-exserted stamens, and a gynophore-borne ovary. The fruit comprises four spreading follicle-like carpels that dehisce to release small reniform seeds.

Boenninghausenia is a small genus of the Rutaceae allied to Ruta, distinguished by its herbaceous habit and stipitate ovary. The pellucid oil glands contain volatile compounds and coumarins, and the plant has a history of use in traditional medicine and as an insect repellent. Variable in leaf division and stature, it has been split into several infraspecific taxa across its wide range. It is common and of least concern, readily recolonising disturbed shady ground.

Author: (Hook.) Meisn. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Rutaceae monograph (Hartley)

Paulowniaceae

Brandisia rosea

by G & P Jürgens

W.W.Sm.

Bhutan2012 413
Bhutan Wangdi 2700m, September

Description

Brandisia rosea is a shrubby, often scandent plant of the eastern Himalaya and adjacent China, recorded by GBIF (about 63 occurrences) from China, India and Bhutan, a small total that reflects its restricted range and rather localised occurrence. It inhabits open forests, thickets, forest margins, scrub and rocky slopes in the warm-temperate montane zone, broadly between 2000 and 3000 m. The plant photographed near Wangdi in Bhutan at about 2700 m in September lies within this band and within the autumn flowering season, when its rosy blooms appear among the post-monsoon vegetation of the eastern Himalayan hillsides, a region where the genus reaches the western edge of its distribution.

It is a woody shrub, sometimes clambering or half-scandent, with young branches and foliage characteristically clothed in a fine stellate or scaly indumentum giving a greyish or rusty cast. The leaves are opposite, simple, ovate to lanceolate, entire or nearly so, and often tomentose beneath. The flowers are showy and borne in the leaf axils or in short clusters; the calyx is campanulate and toothed, and the corolla is conspicuously two-lipped (bilabiate), rose-pink to reddish, with the upper lip arched and the lower spreading and lobed, the form and colour suiting pollination by bees or birds. There are four didynamous stamens. The fruit is a loculicidal capsule containing numerous small seeds.

The genus Brandisia has had an unsettled familial history, long placed in the broadly defined Scrophulariaceae and subsequently reassigned; molecular and morphological studies have aligned it with the small woody clade comprising Paulownia and its relatives, hence its treatment here under Paulowniaceae (it is elsewhere placed in Orobanchaceae by some authors, and its position remains debated). Whatever its precise placement, Brandisia is a distinctive Sino-Himalayan element of montane shrubberies. With its limited range and modest number of records B. rosea has not been formally assessed for conservation, but as a habitat-specific montane shrub it would merit monitoring against forest disturbance in its core eastern Himalayan area.

Author: W.W.Sm. · Sources: POWO (Kew), GBIF, Flora of China Vol. 18, Flora of Bhutan Vol. 2, Flora of Nepal, Hong et al. Scrophulariaceae of China

Araliaceae

Brassaiopsis hainla

by GP Jürgens

Seem.

Bhutan2015 205
Bhutan Zhemgang 910m, October

Description

Brassaiopsis hainla is a small tree or treelet of the eastern Himalaya and adjacent Southeast Asia, distributed from northern India, Nepal and Bhutan through southern China into Myanmar, Thailand, Malaysia and Indonesia. GBIF records some 350 occurrences, the core in China, India, Nepal and Myanmar. It is a plant of subtropical to warm-temperate broad-leaved forest, growing along streamsides, ravine slopes, forest margins and secondary woodland, broadly from the foothills up to around 1500–2000 m. The individual shown was photographed in Bhutan at Zhemgang at 910 m in October, in humid hill forest characteristic of its lower-montane habitat.

The plant is a sparingly branched small tree with stout, often prickly stems and large, palmately lobed or palmately compound leaves clustered toward the branch tips on long petioles; the lobes are oblong-lanceolate, acuminate and serrate, and young growth is frequently armed with scattered prickles. The minute, greenish-white flowers are five-merous and borne in umbels arranged into large terminal, paniculate or racemose compound inflorescences. Each flower has a reduced calyx, free petals and an inferior ovary crowned by a stylar column. The fruit is a small, globose to slightly flattened drupe-like berry, ripening dark, containing several flattened pyrenes.

Brassaiopsis is a genus of the Araliaceae centred on the Sino-Himalaya and Indochina, allied to Aralia and Schefflera and distinguished by its armed stems, palmate leaves and umbellate inflorescences. The young shoots and leaves of B. hainla are eaten as a vegetable in parts of the Himalaya, and the species has local ethnobotanical use. It is reasonably widespread across its montane forest range and is not regarded as globally threatened, though it depends on the persistence of intact broad-leaved forest.

Author: Seem. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, An Annotated Checklist of the Flowering Plants of Nepal, A Systematic Revision of the Genus Brassaiopsis (Araliaceae)

Araliaceae

Brassaiopsis mitis

by GP Jürgens

C.B.Clarke

Bhutan2015 583
Bhutan Gasa 2000m, October
Bhutan2015 590
Bhutan Gasa 2200m, October

Description

Brassaiopsis mitis is an East Himalayan small tree or large shrub of the ginseng family, GBIF holding only about 61 occurrences from India, Bhutan, Nepal and Myanmar. It inhabits humid, shaded broadleaved and evergreen montane forest, occurring along stream gullies, ravine slopes and forest margins generally between about 1500 and 2500 m. The individuals photographed from the Gasa district of northern Bhutan at 2000 and 2200 m, in October, are typical of its occurrence in cool, moist mid-montane forest of deep shade and high humidity, the autumn date corresponding to its fruiting season.

It is an evergreen shrub or small tree to several metres tall, the stems and petioles often prickly, as in many species of Brassaiopsis. The leaves are large, long-petiolate and palmately lobed or palmately compound, the lobes or leaflets entire to serrate, giving the crown a coarse, tropical aspect. The minute, greenish flowers are five-merous with an inferior ovary and are aggregated into umbels grouped into large terminal panicles. The fruit is a small, fleshy, more or less globose drupe crowned by the persistent stylopodium, ripening dark and containing a few flattened pyrenes.

Described by C. B. Clarke, B. mitis belongs to the predominantly Sino-Himalayan and Southeast Asian genus Brassaiopsis within Araliaceae, characterised by prickly, large-leaved understorey trees. With its few records and restricted East Himalayan range it is of regional biogeographic interest, dependent on intact mid-montane forest. Ecologically its umbellate inflorescences attract generalist insects, while its drupaceous fruit is dispersed by frugivorous birds and mammals of the forest interior.

Author: C.B.Clarke · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Lowry & Frodin studies of Brassaiopsis (Araliaceae)

Scrophulariaceae

Buddleja macrostachya

by GP Jürgens

Benth.

Bhutan2015 445
  Bhutan Jakar 2900m, October
Bhutan2015 446
  Bhutan Jakar 3100m, October

Description

Buddleja macrostachya is a widespread Sino-Himalayan and Indochinese shrub, recorded from China, India, Vietnam, Myanmar, Thailand, Bhutan, Bangladesh and Nepal, with over 400 documented occurrences spanning the eastern Himalaya into mainland Southeast Asia. It is a plant of open hillsides, forest margins, thickets, roadsides and disturbed slopes in subtropical to temperate zones, generally between about 1000 and 3200 m. The illustrated plants from Jakar in central Bhutan at 2900 and 3100 m, flowering in October, demonstrate its autumn flowering at the upper end of its altitudinal range, where it forms conspicuous shrubs in sunny, often disturbed montane habitats.

It is a large shrub with quadrangular, densely stellate-tomentose young branches. The leaves are opposite, lanceolate to narrowly elliptic, long-acuminate, with a crenate-serrate margin, dark green and rugose above and grey- to fawn-tomentose beneath, the bases joined by an interpetiolar stipular line. The inflorescence is a long, narrow, interrupted spike-like thyrse (reflected in the epithet macrostachya, large-spiked) of many congested cymose clusters. Individual flowers are small, with a four-lobed campanulate corolla that is pale lilac to pink or purplish with an orange throat, and four included stamens. The fruit is a small, septicidal, two-valved capsule releasing numerous minute seeds.

Although listed here under Scrophulariaceae following the broad APG placement of Buddleja, the genus is also frequently treated in its own family Buddlejaceae; B. macrostachya Benth. is the accepted name. The nectar-rich, fragrant inflorescences attract butterflies, moths and other long-tongued insects, while the light, winged seeds are wind-dispersed. As a vigorous coloniser of open and disturbed ground it is common and widespread, and of least conservation concern.

Author: Benth. · Sources: POWO (Kew), GBIF, Flora of China Vol. 15, Flora of Bhutan Vol. 2, Flora of Nepal, Leeuwenberg The Loganiaceae of Africa and Buddleja revisions (monograph)

Orchideaceae

Bulbophyllum griffithii

by GP Jürgens

Rchb.f.

Bhutan2012 444
Bhutan Wangdi 2500m, September
Bhutan2012 1171 Kopie
Bhutan Tashiyangtse 2000m, October

Description

Bulbophyllum griffithii is an epiphytic orchid distributed from the eastern Himalayas (Nepal, northeast India, Bhutan) through southwest China (Yunnan) to Taiwan. The species is named after William Griffith (1810–1845), the pioneering British botanist who collected extensively in Bhutan and northeast India. It occurs in cool, humid montane forests at elevations of 1,500–2,800 m, favouring mossy tree trunks in the cloud forest zone.

The pseudobulbs are ovoid to subglobose, 1.5–3 cm tall, widely spaced on a stout rhizome. Each bears a single, coriaceous, oblong-elliptic leaf 8–15 cm long. The inflorescence is an umbel-like, subglobose cluster of 5–12 flowers, carried on a slender peduncle 10–20 cm tall — a floral arrangement typical of section Cirrhopetalum. The flowers are about 2 cm across, pale yellow to greenish with purple-red stripes and spots. The dorsal sepal is erect, the lateral sepals elongated and twisted, and the lip is small, curved, and dark purple. Flowering occurs from August to October.

Within the complex taxonomy of Bulbophyllum section Cirrhopetalum, B. griffithii is recognised by its umbellate inflorescence with relatively few, medium-sized flowers and its distinctive striped pattern. GBIF records confirm a limited distribution centred on the eastern Himalayas and East Asia.

Author: Rchb.f. · Sources: POWO (Kew), Flora of Bhutan Vol. 3, GBIF, Pearce & Cribb: The Orchids of Bhutan (2002)

Orchideaceae

Bulbophyllum hirtum

by GP Jürgens

Lindl.

Bhutan2015 573
Bhutan Mo-Chu 1550m, October
Bhutan2015 574
Bhutan Mo-Chu 1550m, October

Description

Bulbophyllum hirtum is an epiphytic orchid distributed across the eastern Himalayas and Southeast Asia, from Nepal and northeast India through Bhutan, Myanmar, southwest China, Thailand, and Vietnam. It grows in warm to temperate broadleaved forests at 500–2,000 m elevation, on moss-covered tree trunks and larger branches, occasionally on rocks near streams.

The plant has ovoid, somewhat compressed pseudobulbs 1.5–2.5 cm tall, spaced 2–5 cm apart on a creeping rhizome. Each pseudobulb bears a single, elliptic-oblong, coriaceous leaf 6–12 cm long. The inflorescence is a lax raceme 5–15 cm long, carrying 5–15 flowers. The specific epithet 'hirtum' (meaning hairy) refers to the distinctive pubescence on the floral parts: the flowers are small, 6–10 mm across, yellowish to brownish-green with conspicuous fine hairs on the sepals and petals. The lip is fleshy, recurved, and densely papillose, dark purple, hinged to the column foot. Flowering occurs from September to November.

Bulbophyllum hirtum is classified within Bulbophyllum section Brachystachya. The pubescent flower surfaces are thought to play a role in pollinator attraction by enhancing both visual texture and scent dispersal, as the genus is predominantly pollinated by small flies (Diptera).

Author: Lindl. · Sources: POWO (Kew), Flora of Bhutan Vol. 3, GBIF, Vermeulen: Orchid Monographs 7: Bulbophyllum (1993)