The 1984 Sino-American Botanical Expedition to Yunnan, China David E. Boufford Bruce Bartholomew A recent expedition to China yielded sixteen hundred flowering plants and ferns from a botanically rich part of that vast country The 1984 Sino-American Expedition to New York Botanical Garden (Bartholomew et Yunnan province, the People’s Republic of al., 1983a). This group, which included both China, was only the second time that authors of this article, was accompanied in American and Chinese botanists were able the field by Chinese botanists from the Insti- to undertake extensive fieldwork together in tute of Botany, Beijmg; the Jiangsu Institute China since Liberation in 1949. Botanical of Botany, Nanjing; the Wuhan Institute of exchanges between the United States and Botany; and the Kunming Institute of Botany. China had begun in 1978, when a delegation One of the two regions visited by that expe- of American botanists, including past Director dition was especially significant because it of the Arnold Arboretum, Dr. Richard A. included the valley in Lichuan Xian (county) Howard, visited China to initiate discussions where the dawn redwood, Metasequoia glyp- on how best to carry out cooperative projects tostroboides Hu & Cheng, grows (Bartho- between botamsts of the two countries lomew et al., 1983b). The Metasequoia valley (Thorhaug, 1978). The following year, 1979, had been the site of the last American col- saw a reciprocal visit to the United States by lecting expedition in China before the country a delegation of Chinese botanists. The dele- was closed to the West more than thirty-one gation visited botanical gardens, arboreta, years previously. and other research facihties throughout the Seeing the largest assemblage of wild country and, in a series of meetings with plants of the dawn redwood (about six thou- their American counterparts at the Univer- sand individuals in this valley) was truly sity of California in Berkeley at the end of exciting, but our group was disappointed to their tour, decided that a joint field expedi- find that the ecological conditions in the area tion in China would be an ideal means of had changed drastically since the previous continuing botanical exchange. expeditions had visited there. The thickets reported by Chu and Cooper (1950), in which and of The First Joint Chinese and American seedlings young plants Metasequoia were had been cleared Expedition: Metasequoia in the Wild found, completely from the base of each Metasequoia tree. The first joint expedition took place between Most of the other trees on the surrounding 15 August and 15 November 1980 and involved hillsides, seen in pictures taken by Gressitt botanists from the Arnold Arboretum; the in 1948 (Gressitt, 1953), had been cut for fuel University of California, Berkeley; the Car- or construction purposes. The existing trees negie Museum of Natural History, Pitts- are now surrounded by rice paddies and fields burgh ; the U.S. National Arboretum; and the of corn instead of natural vegetation, and the 16 human population in the isolated valley has existed before the settling of the valley about increased dramatically! Even though the three hundred years ago, might return. remaining trees have been given full protec- Approximately four days were spent in the tion, once they die they are unlikely to be Metasequoia region, but getting there and replaced naturally under present conditions; back by boat, minibus, and jeep took about the wild populations of Metasequoia will two weeks, and most of the fieldwork during slowly pass out of existence, even though the the 1980 expedition was conducted m the widespread cultivation of the dawn redwood Shennongjia Forest District, a mountainous will ensure the survival of the species. region in northwestern Hubei province. This One interesting observation our group area had been visited previously by Western made during the visit to the Metasequoia botanists, notably by Augustine Henry and region was that only the tree from which the E. H. Wilson, but the interior of the area was type specimens of Metasequoia glyptostro- so rugged and difficult to reach that they boides were collected has a broad, somewhat spent little time there. In the early 1970s the buttressed base. All of the other trees in the Chinese government declared the region a Metasequoia valley, about one hundred kil- "Forest District," a designation roughly ometers from the "type tree" at Modaoqi equivalent to xian (county), and began con- (Modaochi), have smooth, straight trunks structing roads for the harvesting of timber. from ground level to the lowest branches. Roads now connect nearly all parts of the The oldest trees in cultivation in the United district, which allowed our group to reach States are now large enough to show their remote and once isolated areas. mature growth habit, and all of them exhibit In total, we spent six weeks in the Shen- a swollen, slightly buttressed base. It seems nongjia Forest District. Our base camp in the very likely that the large number of seeds village of Jiuhuping, at about fifteen hundred gathered in the late 1940s and widely distrib- meters, was in an area with a climate very uted by E. D. Merrill, then Director of the similar to New England’s, except that central Arnold Arboretum, were from the type tree China receives far more rain throughout the and not from a tree in the main valley. year. The stream along the road in front of Anyone fortunate enough to have trees derived our base camp would rise dramatically after from those first-distributed seeds should be several days of torrential rains, then, because aware of their probably direct descent from of severe deforestation on many slopes, would one of botany’s most famous and historic fall abruptly as the rains were followed by plants. several clear, sunny days. But even without Despite the severe habitat destruction, going outside we could guess at the level of members of the Expedition were able to find the river from the brightness of the electric several plants in the dawn redwood valley lights. Nearly all villages in mountainous that had not been reported previously by regions of China are now supplied with elec- either Gressitt (1953) or Hu (1980). In a sum- mary of our impressions and suggestions for conservation in the Metasequoia valley, the Opposite : Ansaema franchetianum Engler (Araceae), a American and Chinese botanists were unan- relatme of the ~ack-m-the-pulpit of North Amenca Pere Damd collected the this m imous in that several hill- type specimen of species recommending "Tibet onentahs" (i.e., western Sichuan) The plant sides supporting remnants of the original shown here was growmg at an elevation of 2,800 meters forest be set aside and allowed to (9,200 feet) m Yangbi Xian (county), Yunnan provmce regenerate This and all other With photographs accompanymg this naturally. time, something approaching article were taken by Damd E. Boufford, as was that on the original vegetation, which supposedly page 37 17 18 tricity through the widespread use of small (beech), Quercus L. (oak), Betula L. (birch), hydroelectric plants. Each village has a small Sorbus L. (mountain ash), Salix L. /mllow/, generatmg station fed with water channeled Populus L. (aspen), and Tilia L. (basswood). from the main bed of the river somewhere Associated with them, however, were a upstream to a pomt high above the plant. number of plants including Cercidiphyllum The water then plunges through a nearly ver- Sieb. & Zucc. (katsura), Euptelea Sieb. & tical pipe (or pipes) to run the generator. Zucc., and Pterocarya Kunth (wing-nut), When the river was high our lights would endemic to eastern Asia, and Tetracentron burn brightly, but as the level of the water in Oliver, Decaisnea Hooker & Thomson, Dav- the streambed dropped, the lights would idia Baillon, Cyclocarya Iljinskaja (one of the dim, and after several rainless days the elec- wing-nuts, but with the wing completely cir- trical supply became somewhat uncertain. cling the fruit), Sinowilsonia Hemsley, Sino- franchetia (Diels) Hemsley, and a number of or restricted to Plants of Central China others, mostly completely Noteworthy China. The trees around the village belonged to such Many of these genera now known only familiar genera as Acer L. (maple), Fagus L. from China are important in hypotheses Beymg’s mam thoroughfare. 19 regarding evolution and past geographic dis- eastern United States growing in their nat- tributions of plants, particularly of plants in ural environment. Plants that had seemed to the north-temperate regions. One particular be restricted to university campuses, botan- plant, Saruma Oliver (its name being an ical gardens, and arboreta were much more anagram of Asarum L.), a member of the splendid when seen growing from a crevice Aristolochiaceae, resembles our wild ginger in a sheer rock cliff, or intermixed with other in leaf shape and overall appearance, but it trees to form a particular kind of vegetation. has an erect, leafy stem with a flower in each At times, when seeing such plants as leaf axil. The flowers are unusual in that they Viburnum rhytidophyllum Hemsely, Bud- bear both sepals and petals. In wild ginger, dleja davidil Franchet (butterfly-bush), Pach- the stems are creeping and the flowers have ysandra terminalis Sieb. & Zucc. (pach- only sepals (the petaloid structures some- ysandra), or some of the rhododendrons, it times produced in Asarum canadense L. are was hard to understand why they had not actually modified stamens/. Saruma sug- become more widespread in parts of North gests the kind of plants one would guess to Amenca, where the climate seemed so much be the ancestor of Asarum. It is very unlikely, like that of central China. however, that Asarum arose directly from In total, the Chinese and American bota- Saruma, but the similarities and differences in the two genera clearly provide tantalizing clues as to what the ancestor of Asarum might have looked like.