Accepted name: Dendrochilum cobbianum Rchb.f., Gard. Chron. 1880(2): 748 (1880)

Subgenus – Platyclinis. Section – Platyclinis.


 
 
 

Synonyms

 

Platyclinis cobbiana (Rchb.f.) Hemsl., Gard. Chron., n.s., 16: 656 (1881).

Acoridium cobbianum (Rchb.f.) Rolfe, Orchid Rev.: 220 (1904).

Dendrobium cobbianum Rchb.f., Gard. Chron., n.s., 16: 780 (1881), orth. var.

 

Origin in the Wild

 

Luzon and Mindanao

 

Elevation in the Wild

 

1400-2500 metres

 

Habitat in the Wild

 

This species has been collected on Luzon in Benguet Province at Baguio, Mount Data, and Pauai. Within Mountain Province it has been collected from Bauko and on the Bontoc road. Further collections have been made in Rizal Province. On Mindanao this species has been collected in Agusan del Norte on Mount Urdaneta.

 

This species grows as a lithophyte and sometimes as a terrestrial in exposed conditions and within mossy forest. Jim Cootes observed this species growing on rocks in full sun (Cootes 2001).

 

The Plants Description

 

The pseudobulbs cluster on a short rhizome and are shaped fusiform to slenderly ellipsoid. The pseudobulbs measure 2.8-8.2cm long and 0.4-1.7cm in diameter. The pseudobulbs are covered with 4-6 cataphylls when they are growing; the cataphylls disintegrate into persistent fibres as the pseudobulbs mature. The leaves are petiolate; the petiole measures 0.4-8.8cm long. The leaf blades are shaped lanceolate and have obtuse apices. The blades measure 6.0-27.0cm long and 1.5-5.8cm wide. The leaf blades are thin-textured and have 7-9 distinct nerves.

 

The Inflorescence

 

The inflorescence is synanthous and appears with the new growth. The peduncle is suberect to curved and measures 10.2-48cm long. The rachis is pendent and measures 9.2-30.3cm long. The flowers alternate distichously and are spaced 3.0-6.0mm apart. There are 2-5 appressed non floriferous bracts at the base of the rachis.  The flowers open from the proximal section of the rachis.

 

The Flowers

 

Up to 50 flowers can grow on an inflorescence. The flowers are white to yellow or green, the labellum is greenish yellow to orange (Pedersen 1997). The sepals and petals spread widely. The sepals have a few minute trichomes. The dorsal sepal is shaped elliptic to oblong and has an obtuse to acute apex. The dorsal sepal measures 5.0-10.4mm long and 2.1-4.2mm wide. The dorsal sepal is three veined (rarely five veined) and has entire margins. The lateral sepals are usually somewhat oblique, shaped broadly elliptic to ovate-oblong and have obtuse to acute apices. The lateral sepals measure 5.2-10.2mm long and 2.3-4.2mm wide. The lateral sepals are 3-5 veined and have entire margins. The petals are shaped broadly elliptic and have obtuse to acute or subacuminate apices. The petals measure 4.8-9.5mm long and 2.3-4.3mm wide. The petals are three veined (rarely five veined) and have quite entire to slightly irregular margins. The labellum is easily versatile, pendent and 3-lobed. The labellum measures 5.0-8.9mm long and 3.3-6.6mm wide. The labellum is three veined and has serrate margins along the side lobes; the rest of the labellum has entire margins. The side lobes are minute, erect, shaped obliquely triangular and have acute apices. The side lobes are distinctly shorter than the mid-lobe. The mid-lobe is proximally recurved, shaped broadly obovate or obtriangular with a rounded to truncate apex, sometimes slightly irregular or apiculate. There are two short keels that run from base of the labellum and terminate just past the base of the mid-lobe. The column is suberect, slightly incurved and measures 3.0-4.0mm long. The apical wing is prolonged into a truncate apex with a three dentate to finely erose-dentate margin. The apical wing distinctly exceeds the anther cap. The column foot is moderately long. The stelidia grow upwards from the middle of the column, and are subequal to the column apex. The stelidia are shaped linear to narrowly lanceolate, often somewhat falcate and have acute apices.

 

Herbarium Specimens

 

Holotype

 

I could not locate the type

 

Other Herbarium specimens

 

Kew Botanical Gardens (K)

 

Specimen 19467.000

Specimen 43858.000

Specimen K000364861

Specimen K000364956

Specimen K000364950

Specimen 20281.000

Specimen K000364832

National Herbarium, Netherlands, Leiden (L)

 

Specimen L0322424

Specimen L0322425

Specimen L0322426

Specimen L0322427

Specimen L0322428

 

Scent

 

Yes

 

Flowering Season

 

Flowers have been collected in the wild from April to June and from August to December. Flowering plants in my collection generally flower from winter to spring.

 

Culture

 

This is one of the most commonly seen Dendrochilum in cultivation.

 

This species, when grown well, quickly becomes a specimen plant and can double in size each year. This plant is generally quite easy to cultivate.

 

This plant should be given a very short period of rest after it finishes flowering, allow the plant to dry slightly between watering for a period of two weeks after when normal watering can re-convene.

 

Similar Species

 

Dendrochilum amesianum

Dendrochilum pangasinanense

 

Other Information

 

The epithet refers to the first person to flower this plant in the UK, Walter Cobb (Cootes 2001).

 

The flowers are usually white with a yellow or orange lip but other varieties exist. The cultivars commonly found in cultivation are:

 

Dendrochilum cobbianum 'Chartreuse Sentinel' (large flowers, sturdy succulent leaves)

Dendrochilum cobbianum 'Fat Leaf' (chartreuse flowers with yellow lip)

Dendrochilum cobbianum "Gold Chain" (with glittering, golden, fragrant flowers)

Dendrochilum cobbianum "Green white" (with long spikes of fragrant, green-white flowers)

Dendrochilum cobbianum 'Sentinel 1' (yellow flowers)

Dendrochilum cobbianum 'Sentinel's Poco' (miniature creamy flowers with yellow lip)

Dendrochilum cobbianum "Yellow Sentinel" (yellow flower with darker yellow lip)

 

This species is often seen mislabelled as other species.

 

There is a nectar gland in the centre of the labellum (Cootes et al 1995).

 

Reference -

 

AMES, Oakes. 1908, Illustrations and studies of the Family Orchidaceae Facsimile 2, Ames Botanical Laboratory, North Easton, Massachusetts, Boston.

 

COOTES, Jim. The Orchids of the Philippines, 2001. Timber Press, USA

 

COOTES, Jim. BANKS, David. 1995, The genus Dendrochilum A guide to the species in cultivation, Orchids Australia, AOC

 

PEDERSEN, Henrik. 1997, The Genus Dendrochilum (Orchidaceae) in the Philippines - A Taxonomic Revision. Opera Botanica, Denmark

 

World Checklist of Selected Plant Families. 17 January 2009. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 17 January 2009.