Mysterious Maid of the Mountains--The Taiwan Pleione

After the spring break around Tomb Sweeping Day (5 April), successive rainstorms on Mt. Ali knock most of the cherry blossoms to the ground, leaving the few still on the branches looking somewhat forlorn. But under several tall cherries in front of the old Mt. Ali forestry station, a slope is covered with the pink and purple flowers of the Taiwan pleione (Pleione formosana), their slightly raised "lips" glistening with a sprinkling of morning rain. The sight of these fresh, tender flowers, undamaged by the rain and illuminated by the first rays of sunshine to penetrate here for many days, elicits delighted comments from many visitors.

Faces washed by spring rain

Of all the artificially cultivated flowering plants, orchids have become the most specialized. Through crossbreeding and hybridization, orchids of the same species have been made to produce hundreds of different varieties in a dazzling array of shapes and hues. Yet when it comes to creating varieties, the greatest master is nature herself. A century ago, the great variation in the flowers and bulbs of Taiwan's wild pleiones baffled the botanists who attempted to classify them.

By April 1909, the Japanese had begun large-scale logging of Mt. Ali's false cypress trees. Many Japanese were also attracted by the rich plant life of the area's forests, and it was then that the Taiwan pleione was first recorded and named. A pleione from Mt. Ali-the first to appear on the international stage-had a 20-centimeter inflorescence (flower-bearing stem) with two bright red flowers, each with four "keels" (raised folds of tissue) on its "lip" (or "labellum"-the lowest of an orchid flower's three petals, specially shaped to attract pollinating insects).

In the winter of 1912, a collector named Price from Britain's Royal Botanic Gardens also came to Taiwan, and collected pleione bulbs from Ilan in the north of the island. But after they were sent back to Kew, England to flower and be identified, it was found that the inflorescences were only five centimeters long, and bore only one flower, colored purple or pink, with only two keels on the lip. They were so different in appearance from the first recorded Taiwanese pleiones that they were judged to be a different species.

Two decades later, the Japanese botanist Fukuyama Noriaki also collected pleiones from Mt. Hsiakalo in Hsinchu. This time the flowers were a pure, snowy white, and the onion-like bulbs were a glistening green color, unlike the previously discovered purple bulbs. Overjoyed at his discovery, Fukuyama named this new variety the snow-white pleione (Pleione formosana var. nivea).

But the pleiones discovered in different parts of Taiwan gradually raised doubts among scientists, who began a long process of research and comparison.

A sprig of green jade

Throughout the world, over 20 species of wild pleiones have been recorded. Their common features are that they produce "pseudobulbs" to store water and nutrients, and each pseudobulb grows only one leaf and usually bears only one flower.

Though bearing a solitary leaf and flower, the pleiones stand out among the many different orchids for their large, showy blooms five to six centimeters across. Their lips are specially evolved into trumpet shapes, often with a lacy fringe, and are surrounded by three long spatula-shaped sepals. They are no less attractive than hybrid Cattleya orchids, and have long numbered among the plants botanical collectors most hope to happen upon when tramping through the mountains.

As botanists from the 19th-century colonial powers collected specimens from all over the world, they discovered that pleiones were native only to Asia. From the Himalayan foothills of India and Nepal to Yunnan and Sichuan in China, pleiones were found in many shapes and colors, some with unique fragrances.

Foresters and plant collectors traversing the mountain forests of Taiwan noticed that pleiones of different colors, and with different inflorescence characteristics and lip configurations, often bloomed together, and snow-white specimens occasionally grew amidst populations of other varieties. Hence botanists determined that Taiwan has only one species of pleione, but its flowers show many variations and it often appears in "intermediate" forms with slight differences of biology. Also, Taiwan's terrain is rugged and diverse, with habitats separated by high mountains and rivers, so pleione populations in different areas are often distinct from each other. These differences initially confused botanists, and the taxonomy of Taiwan's pleiones was not settled for almost a century.

Once this "girl of a thousand faces" emerged from the mountains, she became an international star. Although the Taiwan pleione was only given a scientific name in 1911, by 1914 it was already an honored guest at Kew Gardens. From 1920 to 1975, Taiwan pleiones won six major orchid prizes in Britain, a record for the pleione genus.

Because of the pleione's great popularity in the West, Taiwan has a long history of exporting wild pleiones. The pleiones of Mt. Taiping in Ilan County have much larger bulbs and blooms than those of other areas, so their bulbs were harvested in huge quantities by orchid merchants, at the rate of over a million each year.

However, unlike our native butterfly orchids, people in Taiwan have never known much about the pleiones which grow on our home soil, despite their being exported in large numbers and enjoying such a high reputation internationally.

Expert rock climbers

Taiwan has over 400 species of wild orchids. Pleiones mainly grow in the mountains at medium elevations, between 1,500 and 2,500 meters above sea level. In the wild, they are seen mostly on steep rock faces. Research fellow Yao Chen-te of the Taiwan Endemic Species Research Institute first encountered pleiones while he was surveying wild birds. Lifting his head and looking across at a far-off cliff face, he noticed that it was densely covered in little purple flowers. He took up his binoculars for a closer look, and saw an expanse of beautifully colored pleiones. He was so intoxicated by this magnificent scene that he recounted his vision to everyone he met.

Professor Su Hung-chieh of National Taiwan University's Department of Forestry, who was the first person to research wild orchids in Taiwan after the island's return to Chinese rule in 1945, classes the Taiwan pleione as an early-stage plant in the "succession" of vegetation types which colonize bare rocks. On exposed, eroded rocks, accumulations of rainwater, moss and plant debris create thick pockets of loose humus, which provide the right environment for pleiones to grow. As well as needing the protection of mosses, pleiones both crave and fear the sun. They cannot bear strong direct sunlight, so the rocks where they grow have to be shaded by large trees.

In their struggle for survival amid the myriad species of trees and herbaceous plants, orchids have developed a dazzling variety of lifestyles. To avoid the intense competition at ground level, the Taiwan pleione has evolved into an expert "rock climber." Along the Old Ssumakussu Trail in the mountains of Hsinchu County, pleiones grow on the trunks of the immense ancient trees, and walkers have the company of beautiful wild orchids all the way.

Pleiones do not grow in soil, so except for the water they are able to get from rain showers, most of the time they rely on moisture in the air. This is why they prefer to grow in the mist-shrouded cypress, and their leaves are equipped with wrinkles to trap water vapor.

Unfortunately for the pleiones, the cypress forests were also long Taiwan's main commercial forests, and after logging, foresters cleared whole stretches of land for replanting. The rich forest flora was swept away, and the Taiwan pleione, just like the false cypresses, became a rare species.

Bearing orchids from the mountains?

Apart from the damage done by logging, forest clearance for farming, and the collection of pleiones for export, the most destructive threat to pleiones is Taiwanese people's unwillingness to return "empty-handed" from trips into the mountains. Huge areas have been stripped almost bare of pleiones by tourists and flower merchants.

Sadly, when the pleione bulbs come down to the plains, despite being lavished with care morning and night by their proud owners, if they have not gone through a period of dormancy at low temperatures their flowering season will come and go without them producing a single bud. The artificially grown pleiones that appeared on the market in the early 1980s fared little better. In the subtropical lowlands of Taiwan, once the flowers had faded, if the plants were not taken back into the mountains then the following year their pseudobulbs would gradually wither and die. Thus on flower markets today you can see orchids of every description on offer, but rarely will you find a pleione among them.

Once seen all over Taiwan at medium elevations, today pleiones only survive at a few scattered mountain locations. But at least at Mt. Ali, thanks to past human activities, they are still able to hold their own against the flowering cherries and rhododendrons in the spring flowering season. Years ago, the Japanese built the Mienyueh branch of the Alishan Mountain Railway to gain access to the cypress forests for logging. As the engineers cut their way along mountainsides and hacked out tunnels, they exposed large areas of steep rock face shaded by dense jungle above, and thus unwittingly produced excellent conditions for pleiones to grow.

In 1992, after a survey of pleiones along the Mienyueh branch line, the Taiwan Forestry Bureau (TFB) designated a Taiwan Pleione Nature Reserve there under the Cultural Heritage Preservation Law, and allowed tourists access to admire the flowers. It was only then that people in Taiwan realized that on their own island there was still such a "lonely valley of the orchids."

To better understand the plants' life cycle and living environment, Cheng Mei-li, an assistant technician at the TFB's Chiayi Forest District Office, has spent six years observing and monitoring pleione growth.

Cool winds, bright moon, serene orchids

The pleiones of the Mienyueh nature reserve mark the rhythm of the passing seasons in the mountains. In May their blossoms fade, wither and fall as summer arrives bringing ample sunshine and increased rainfall. The pleiones' leaves grow faster and photosynthesize large quantities of nutrients, which are stored in their rapidly growing pseudobulbs. At the same time, the buds for next year's flowers also form.

When autumn comes, the pleiones' leaves succumb to the frosts and gradually turn yellow. "Their biological clock is tuned to the seasons. There's a precise timing to when they flower, when their leaves grow and when their leaves fall-they're never late," says Cheng Mei-li. In winter, daytime temperatures on Mt. Ali fall below 10oC, and night often brings a light dusting of frost. At this time the pleiones shed their leaves and die back to leave just the bulbs, which become dormant for a full four months or more, buried in a thick carpet of moss which keeps them warm and moist.

At the first breath of spring, the buried bulbs come back to life. Unlike other orchids which flower alone and easily go unnoticed, when warmed by the sun and mild breezes Taiwan pleiones flower together in their thousands, suddenly bringing a splash of spring color to the formerly drab rock faces, and attracting countless bees to carry pollen from blossom to blossom. Pollinated flowers quickly wither, and their ovaries swell and develop into spindle-shaped seed capsules holding 100,000 seeds each. When the seeds are mature the capsules burst open and the seeds are spread by the wind. If they settle somewhere suitable they will germinate and grow into new plants, which take four years to flower for the first time.

"If only people don't destroy their habitat or pick them, I'm sure pleiones can thrive on Mt. Ali for a long time to come," says Cheng Mei-li, who hopes that the past home of the false cypresses can continue to be the home of the pleiones forever.

Mountain flowers

"The orchid is a mountain plant;/ Grow it in the mountains./ Too many are planted in pots in our dusty world;/ Better to leave them in the company of the mists and the sunset." Zheng Banqiao's poem from the early years of the Qing dynasty expresses the hope that orchids can return to the wild places where they belong. In fact this was the poet's cry for the freedom of his own spirit; but from the point of view of modern biology, today's mass-produced hothouse orchids are rarely equal to the rigors of the environments they are placed into, and their faded, jaded appearance is a far cry from the beauty of a wild orchid.

For true flower lovers, the shy orchids of the wild are just as precious as the oversized local or exotic orchids grown in private gardens. Surely flower lovers hope that just like priceless cultivated Cymbidium orchids, the faraway orchids of lonely valleys will always find a corner where they can survive.

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A sprig of red, fragrant in the dew. The pleione's tender lips attract not only bees and butterflies, but also the covetous attention of flower lovers-so much so that it has almost disappeared from Taiwan's mountains.

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The Mienyueh nature reserve, deep in the Mt. Ali range, has become the last homeland of the Taiwan pleione. Looking across from the Chaoping station of the Alishan Mountain Railway, that place of swirling mists is Mt. Tata, where the reserve is located.

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The pleiones change their face to fit the seasons: in spring, their flowers bloom; in summer, their leaves grow large and fat; when autumn winds blow, their leaves yellow and fall, leaving only the bulbs to wait hidden in the moss until the next spring, when they will blossom again with renewed vitality. (courtesy of Cheng Mei-li)

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The Taiwan pleione, which quenches its thirst with drafts of mist and dew, grows mainly on mountain slopes thick with moss. Our picture shows pleiones beside the presidential lodge on Mt. Ali.

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Assistant technician Cheng Mei-li of the Taiwan Forestry Bureau has spent six years studying the natural history of the pleiones in the Mienyueh nature reserve, and has written a book about them.