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ERIA

Category: Plants and Orchids
Date Posted: 2006-10-16

FOUR LARGE GENERA, DENDROBIUM, BULBOPHYLLUM, DENDROCHILUM AND ERIA, comprise almost one-third of the species of the Philippine orchid flora. Of these four, the genus Bulbophyllum is the largest; the genus Dendrobium includes the greatest number of species of horticultural interest; while the genera Dendrochilum and Eria are large groups of small flowered species which are of interest only because of their delicate many-flowered racemes.

There are probably more than three hundred species of Eria distributed throughout southeast Asia and the surrounding islands and of the almost eighty which are indigenous to the Philippines, possibly sixty art endemic. This is an extremely polymorphic group of allied species, which differ to a marked degree in the habit of the plants and as a result the genus has been subdivided into a number of sections for easier classification and I study. Eria was originally described as a genus by Lindley and the name means "woolly," in reference to the woolly or downy flowers of some of the species. This genus is similar and allied to the Dendrobium, and the flowers resemble those of that genus in shape but differ 6otanically in having eight pollen masses instead of four. The pollen masses are united into one or two bundles, instead of being free.

The genus Eria is widely distributed throughout the islands and different Species grow under extremely divergent climatic and geographical environments. Some are native to the hot low areas at sea level, while others thrive in the cooler moist forests above six thousand feet elevation; in between these extremes are found the many species which make up che Philippine portion of this genus.

Although the greater number of native species are epiphytic, several are terrestrial or semiterrestrial and can be found growing in the humus collected among the rocks or in the crotches of large trees. Included within the genus are some of the smallest orchids with exquisite miniature flowers as well as some of the largest with pseudo-bulbs two or three feet long. The flowers of a number of species develop singly; however,in many of them the inflorescence is a short lateral or semierect many-flowered spike which is produced from near the apex of the pseudo-bulb leaving a characteristic depression or clearly defined hole as a scar of the inflorescence.

This genus is one of the most interesting of the "botanical" type of native orchids and although the flowers are small, their clusters are colorful and readily justify their common name, "Lily of the Valley Orchid."

Eria Javanica is a species which has a wide distribution throughout the Malaysia area including-the islands of Amboina, Celebes, Java and the Philippines. This species can be considered a semiterrestrial, for it -is often found growing in a rich humus material that collects in the crotches of trees. The large four-angled pseudo-bulbs, which are about three inches high and 1 1/2 to two inches thick, are terminated by a single lance-shaped leaf which is prominently veined and about twelve inches long and two inches wide. The flower stems develop between the leaves and the pseudo-bulb and !eaf is often two feet tall. The flowers of a single inflorescence open in groups on separate occasions over a period of a few weeks during June and July. The whitish flowers are small, about three-quarters of an inch across and remain open for about four or five days. The authors collected the species from the Lucban area of Quezon Province, where it was growing at an altitude of about fifteen hundred feet. This species received its specific name Javanica in reference to the Island of java, where it is also indigenous.

Eria Lyonii is a common species, which can be collected from the Sierra Madre Mountains of eastern Luzon at an elevation of about two thousand feet. These plants grow on the top of the tall forest trees along with a congested growth of tropical ferns and other orchids. The pseudo-bulbs are ovoid, about 1 1/2 inches high, and are joined at the base by a short, thick rhizome. The gracefully recurved leaves develop from the top of the pseudo-bulbs and are eight to twelve inches long with prominent veins. The inflorescence arises from the summit of the pseudo-bulbs and is ten to twelve inches tall Individual flowers, which all appear at the same time, during April through July, are white with recurved sepals and petals that are clearly lined with dull purple lines on their inner surface. The labellum is clear white with a yellow base. This species is probably dedicated to Lyon, an orchid fancier and resident of Manila during the first quarter of the twentieth century.

Eria cylindrostachya has a thickened stem or pseudo-bulb about two to three inches long and three-quarters of an inch thick, which when immature is covered with a distichous bract. These stems, which are also rough and furrowed, are terminated with two leathery leaves about four inches long and one inch wide. The inflorescence is a compact cylindrical raceme of small flowers and is about six inches long. On this there are from sixty to eighty individual greenish white and slightly waxy blossoms, each about one-quarter of an inch across.

The authors have collected these plants from the neighborhood of Baguio, where they were growing on rocks as well as on trees. This species is a mountain plant and has slep been reported from Mount Apo, Mindanao, as well as Mt. Mariveles, Bataan, Luzon. It flowers during April, USy, . and. June.

The specific name cylindrostachya probably refers to the cylindrical shape of the flower spikes.