Vietnam Cycad and Palm Expedition (Part I)
In 1994 1 conducted a two month research expedition to Vietnam sponsored by The Montgomery Foundation and Fairchild Tropical Garden of Florida, U.S.A. Vietnam is a tropical country with a rich flora, with many unique species of plants. It is also a country that has been racked by continuous warfare for the last half century. There has been little botanical exploration in this country since French colonial times and much of what is known of the cycads and palms is from that period.
My expedition into Vietnam began October 16, 1994 at the border with China. I crossed from Yunnan Province, China, into Vietnam at the village of Lao Cai. On the Chinese side most of the vegetation had been cleared for agriculture, but the Vietnamese side is still heavily forested. At Lao Cai I tried hiring a vehicle and guide to explore the countryside, but I soon found that the surrounding hills had been mined during the China-Vietnam border war of the 1970's. I decided to travel south by train to the capital city of Hanoi.
The train to Hanoi departed five hours behind schedule. The ride was very bumpy, as the tracks were built some 100 years previously by the French. I did not sleep during the 15 hour ride as my seat was hard and uncomfortable. I began to realize that field work in Vietnam would require even more patience and energy than my home country of China In Hanoi I met Dr. Nguyen Tien Hiep of the Institute of Ecology and Biological Resources. Dr. Hiep and his Institute would be the sponsor for my expedition. I was also joined by Mr. Anders Lindstrom of Sweden. After studying dried herbarium specimens at the Institute we began our excursions into the field.
Cycas bellefonti at Cat Ba Islands
East of Hanoi, and just off the coast from the port of Haiphong, are a group of islands that have been designated a national park, the Cat Ba Islands National Park. At the park headquarters are displays showing the topography and habitats around the island which includes tropical evergreen forests, mangrove swamps, and coral reefs. Fifteen species of mammal are protected on the islands including the Franqois Monkey (Presbytis francoisi) and wild boar, as well as 21 species of birds. Some 620 species of plants are recorded on the island including a species of cycad. After a short search we found this cycad growing on limestone cliffs (Fig. 1,2). The plants grew out off edges and fissures in the hard metamorphic limestone. This limestone formation, like almost all the ones I've encountered in south east Asia, are eroded into sharp peaks and edges. One slip would almost certainly be fatal. This cycad matched the description of Cycas bellefonti by Lindem & Rodigas from more than a century ago. Like much of these old descriptions the exact location and habitat were not recorded. Since the original description no studies had been done on this species. It is a very attractive cycad with relatively short leaves. Its leaflets display wavy edges especially when grown in shade. The seeds were quite small for a Cycas, only 2cm diameter or less. On the Cat Ba Islands we also found three species of the rattan palm Calamus, as well as unidentified species of Caryota, Licuala, Livistona and Phoenix.
South of Tonkin
From Cat Ba we travelled inland 60km west of Hanoi to an area known since colonial times as Tonkin. This is an area of karst terrain composed of rugged hills and steep limestone mountains. I was determined to find the source of a cycad I saw being grown as pot plants in the city of Hanoi. This species had relatively small trunks and leaves and I believed them to be Cycas miquelii Warburg. In this limestone region we were joined by Professor Phan Ke Loc of the University of Hanoi who is an avid student of the flora of these limestone hills. Our rented Russian jeep was now very crowded. In this region we observed Caryota bacsonensis (Fig. 3), Arenga pinnata, and a palm with seeds 2cm in diameter which I tentatively believe to be Livistona cochinchinensis. At one spot along the road near a lake we found villagers selling Cycas plants. They stored the plants in water at the lake's edge to keep them fresh. Near the town of Chi Ni we found a population of cycads on the southern face of a cliff (Fig. 4). The cliff was unscalable, but seedlings growing at the base suggest that they were similar if not identical to the cycad growing in Hanoi. This species probably inhabits an extensire area reaching into China and appears to display a variety of leaf shapes throughout its range.
We continued south to the town of Nghia Dan. This is the type locality for Cycas chevalieri Leandri, a species with a subterranean trunk and large leaves similar to Cycas micholitzii var. simplicipinna, described from Thailand. This area was the site of an old French agricultural station, which is now long gone. We found three cultivated specimens in a nearby town that matched the description of the plant. In three days of searching our local guide lead us to Livistona humilis, Caryota sp. and Cycas siamensis Miquel, but C. chevalieri was not to be found in the wild. For me this species will remain a mystery!