By Jim Cootes and Ronny Boos
This is a continuation of an article on the Dendrobium section Calcarifera, which was published in this newspaper on December 3, 2017.
As was mentioned, in the previous article, the members of section Calcarifera can be divided into two groups based on the growth habit of the plants, which in this case are totally pendulous, and the number of flowers, usually one or two, produced on the inflorescence(s.)
Dendrobium ceraula was first described by Professor Heinrich G. Reichenbach (1824-1889) in 1876, but was also described, in 1938, as Dendrobium gonzalesii by Dr. Eduardo Quisumbing (1895-1986). This species is only known from the provinces of southern Luzon, where it grows at elevations above 1,300 meters. An extremely variable species color-wise.
Dendrobium victoriae-reginae (Jim Cootes)
Dendrobium serratilabium (Georg Hampel and Jim Cootes)
Dendrobium ceraula (Jim Cootes)
Dendrobium chameleon (Ronny Boos and Jim Cootes)
Dendrobium chameleon var. ovatilabium (Ronny Boos)
Dendrobium yeageri (Jim Cootes)
Dendrobium crassimarginatum (Jim Cootes)
Dendrobium chameleon has pure white blooms with varying degrees of red striping on the sepals and petals. It is known from the mountains of southern Taiwan. In the Philippines it is recorded from the provinces of Benguet, Laguna, the Mountain Province, Pampanga, and Sorsogon on Luzon. This species is usually found at elevations above 1,000 meters.
Dendrobium chameleon var. ovatilabium differs from the nominate form by its large egg-shaped labellum. This variety occurs in the mountains of Benguet and Pampanga on Luzon; and on the island of Mindoro. It favours habitats of over 1,000 meters elevation.
Dendrobium crassimarginatum is seldom seen, and the only plants we have observed in the wild were in the Visayas. The pure white flowers, which are fragrant, make this one of the most outstanding members of the section. It grows on the mossy branches of trees at elevations of between 600 and 1,000 meters.
Dendrobium serratilabium is the most wonderfully variable species, color-wise, in this section. The structure of the labellum is one of Mother Nature’s true wonders. The purpose of the labellum is not to amuse us humans with its intricacies, but to provide a landing platform for the pollinator, which one would suspect is a butterfly. This wonderful species has been recorded from the provinces of Aurora, Laguna, Quezon, and Rizal on Luzon; the Visayan island of Leyte; and the province of Bukidnon, and Misamis on Mindanao. It inhabits mossy forest at elevations of between 500 and 1,200 meters. Dendrobium serratilabium is the most widely distributed species of section Calcarifera, in the Philippines.
Dendrobium victoriae-reginae is one of the few orchid species which has true blue flowers, but there are also pure white, and violet colored forms of this most magnificent species. It has been found in the provinces of Ifugao, the Mountain Province, Nueva Ecija, Nueva Vizcaya, Pampanga, and Quezon, the island of Mindoro; the Visayan island of Negros; the island of Camiguin de Mindanao and the province of Davao on Mindanao. This plant is found at elevations of over 1,300 meters.
Dendrobium yeageri is closely related to Dendrobium victoriae-reginae, but usually the flowers are in the pinkish shades. This beautiful species is only known from the provinces of Benguet and the Mountain Province on Luzon. It is usually found at elevations of between 1,000 and 2,000 meters.
As can be observed from the above information the species from section Calcarifera are all high elevation plants. Being from such habitats they will not grow successfully in the high temperatures of the lowlands. The plants should be left in their natural habitat for the enjoyment of future generations.
Part 3 will appear next week.