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Huai thung choa highland project

The huai thung choa highland project: Status and opportunities

Pisit Voraurai, Jack D. Ives, and Bruno Messerli


The Huai Thung Choa Highland Project was initiated in 1975 under the leadership of Dr. Pisit Voraurai and Prakorn Jringsoongnoen as a joint undertaking between the Royal Department of Forestry and Chiang Mai University. The project field area is situated in the mountains some 60 km northwest of Chiang Mai and extends in elevation between about 800 and 2,000 m. Originally the field area was confined to a number of small drainage basins tributary to the Mai Ping, although current plans are to extend across the continental divide, taking in two or three small drainage basins tributary to the Salween River. This will thus encompass villages of the Hmong as well as those of the Lisu and Karen that are already incorporated. This would add approximately 120 kmē to the existing 220 kmē of the original field area.

The area embraces a series of distinct altitudinal belts extending across the Highland-Lowland Transitional Zone of Uhlig (see page 33) into the higher parts of the Mountain Zone Thus the area contains a transect from the transitional zone forests. through to the Lower Montane Forests and some of the highest summits in Thailand, it also brackets the zones of contact and land-use conflict between ethnic Northern Thai, pushing up into the transitional zone, and Karen. Lisu, and Hmong at successively higher levels.

The field area is geomorphologically typical of much of the highland area of Northern Thailand, being a mosaic of long, smooth ridge crests: steep slopes; numerous steep-sided tertiary drainage basins; and occasional deeper and wider valleys. The primary slopes are very steep, frequently 30° to 45 . and provide the main elements of a complex fluvial landscape of medium relief characteristic of monsoonal Asia (Figs. 1 and 2). Most of the primary Upper Montane Forest has been destroyed and only pockets remain on steeper slopes or in the more inaccessible small watersheds at higher levels (Fig. 3). This is because the area has been subjected to different forms of swidden agriculture over many generations. including the more destructive forms of the Hmong and Lisu that include opium cultivation. Thus extensive areas, including steep slopes. have been denuded, or partially denuded, of forest (even secondary forest) cover, and Imperata grassland. as successional to repeated forest firing, is very extensive in certain areas.

The original Huai Thung Choa Highland Project combined a number of related objectives to meet two major targets. These are: (1 ) watershed conservation; and (2) improvement of local living standards on an ecologically balanced basis which is a vital prerequisite for watershed conservation. Pursuit of these two major targets has resulted in a number of practical undertakings including: development of a large, well-equipped field station at 1,100 m elevation in the centre of the project area that contains housing for visiting scientists and family housing of more traditional design for imported Thai and highland ethnic workers: a large horticultural research area. with nurseries and greenhouses; a field hospital; a school adjacent to the field station, equipped for education of Karen, Lisu, Thai, and ultimately for Hmong children: a road and communications network; and several pine plantation nurseries in support of an extensive reforestation programme.

Thus the research being undertaken at the time of the first United Nations University field evaluation mission (April 1978) was principally forestry and horticulture together with a great deal of applied socio-economic activity which involved health, education, and incorporation of the local ethnic people into the forestry and horticultural activities. The NRP staff believed that this original preexisting project was sufficiently well founded and relevant for its adoption and enlargement under the auspices of the Agro-forestry Systems and Highland-Lowland Interactive Systems subprojects.

Status of the Huai Thung Choa Project

The Huai Thung Choa Project is one of 32 watershed management units established by His Majesty King Bhumibol Adulyaduj as a "King's Project." The project combines extensive reforestation with horticultural experimentation as a basis for introduction of alternate cash crops to replace opium and to help stabilize the existing swidden agricultural practices. Thus it is central to the contemporary expression of concern for tackling the growing environmental disequilibrium in the Northern Thai mountains resulting from rapid growth of population on the traditional forms of swidden agriculture, and the penetration of the area of increasingly market-orientated activities from the neighbouring lowlands. The project area embrances 2 Lisu, 8 Karen, 1 Hmong, and 16 Thai villages with a total population of 2,350 in 27 separate villages. The attention to health and educational needs has developed as an integral part of indirect and direct attempts to modify the land-use practices of the local people while at the same time planning for preservation of much of their original culture.


Some 15 ha of land have been cleared for development of gardens and experimental plots for selecting the most appropriate varieties and species of flowers, seed flowers and bulbs, fruit, vegetable. nut trees, mushrooms, and tea. The horticultural activities have two major components: first. selection of species and varieties for widespread introduction into the hinterland; and. second, actual production of cut flowers, bulbs. seeds, and market garden products for sale in Chiang Mai, Bangkok, and. in the case of cut flowers, as far afield as Singapore and Hong Kong. An integral part of this development is the direct employment of Karen and Lisu people as wage earners in the research and market gardening areas. Thus there is a clear attempt to lure Karen and Lisu away from dependency on opium production and to explore the means of developing more intensive forms of land use than the existing landextensive swiddening. In this respect it is worth emphasizing that the Karen, Lisu, and Hmong constitute a tribal hierarchy for opium production The Hmong grow opium and subsistence products and act as general traders; the Lisu grow opium and usually sell it to itinerant Chinese traders. Neither the Hmong nor Lisu are generally addicted, but many Karen are in part because they provide much of the labour in opium production and the Hmong and Lisu pay for as much of this labour as possible with some of the opium produced. Consequently the Karen have the lowest status, and are extensively addicted.

However. by employing Karen in the horticultural undertaking at wages that ensure a higher standard of living than can be derived from their traditional system, the Huai Thung Choa Project is taking some initial steps to break the opium production chain. A parallel step was taken by persuasion of two of the senior Lisu families of the immediately adjacent village to attempt horticultural activities as a substitute for opium production on a two-year trial basis. The objective here was to convince influential Lisu that recourse to horticulture would provide a higher standard of living than their traditional form of swidden-subsistence agriculture supplemented by opium. Since numerous middle men in the opium proportion of the profits. for the poppy grower, potato production, given a direct marketing system. can yield considerably higher profits. It is not surprising that the first steps in this approach have succeeded. Thus the two Lisu families have been at least temporarily convinced, and have (as of the November 1978 field visit) persuaded the entire village to substitute horticulture for opium production.

The prospects for development and much wider application of this approach are very good. although such optimism is dependent upon an important factor. The existing Huai Thung Choa situation has benefited from the large input of government funding. For instance, the road system, introduction of many dozen species and varieties of flowers, fruits. and vegetable, wage labour. and the beginnings of a marketing system. render the project as a special, highly subsidized case. Development and maintenance of a reliable marketing system will prove critical and the question of self-sufficiency on a long-term basis remains to be answered.


Extensive areas are being reforested using Pinus kesiya as the principal species Seedling production is undertaken locally in several nurseries adjacent to native villages. so that another form of wage labour has been introduced. P. kesiya is a fast-growing native Thai pine. It is valuable as a provider of ground cover against torrential rain impact. and for fuelwood, stakes. and posts, but is of limited value for lumber and construction Introduction of seedlings into Imperata grassland requires extensive mechanically assisted efforts to break through the Imperata root-mat A major problem is recurring forest fires and there is as much as 30 to 40 per cent loss in new forest plantations. This is partly due to escape fires moving from the supposedly controlled burning of the swidden activities, and possibly also to deliberate arson during periods of individual or group stress. The high failure rate in the reforestation scheme may prove a major obstacle to success of the overall project. and since forest clearing is part of the core tradition of the hill peoples, it may prove extremely difficult to correct. However, an optimistic note was sounded in November 1978 when Lisu villagers committed to horticulture promised to stop burning forested areas in the future. Again, first critical steps have been taken to ensure extension of significant changes in traditional land-use practices. Nevertheless, the longer-term problems of induced changes in traditional practices, mentioned elsewhere in these proceedings, must be carefully borne in mind.

Landscape Deterioration in the Field Project Area

The extensive development of Imperata grassland (and assumed changes in the hydrological cycle). is apparent to the casual visitor (Figs. 4 and 5). However, despite use of very steep slopes (45° slopes are frequent with a local relief of 300 to 400 m), large-scale slope instability is not particularly widespread. An exception to this is deep gullying and small mudflows related to the growing extent of bulldozed dirt roads (see Messerli, p. 59, Fig 5, this volume). Thus during the field insecption in November 1978 we looked for evidence of soil erosion due to sheet wash. While this investigation was very limited both in time and extent, the preliminary results indicate such catastrophic losses that they are introduced here for future testing.

Two Lisu fields were chosen for preliminary investigations Both were at about 1,200 m altitude and were north facing with 40- to 45 mid-slopes. One had been cleared by forest cutting and burning the previous spring (March-April 1978) while the other had been prepared for agriculture one full year earlier. Thus, the first had experienced a single monsoon season after clearing, while the second had been farmed for two seasons. Soil pits were dug at the ridge crest. mid-slope, and foot-slope in each field The results are shown schematically in Fig. 6 (see photos, Figs. 7 and 8). What becomes apparent is that while a significant amount of top soil (A horizon) has been lost from the first field, the losses from the second field. amounting to the entire A horizon and most of the B horizon, are catastrophic. The lower part of Fig. 6 is a schematic reconstruction from scattered soil pit data, indicating degree of recovery of soil structure and fertility following a minimum of 20 years of forest fallow.' Soil pit sites were chosen on the advice of the Lisu farmers backed by estimated tree ring counts. From this it is clear that forest fallow of less than twenty years will result in eventual destruction of the local natural resource base for human population. Further pedological reconnaissance revealed the existence of multiple and inverted A, B, and C horizons in poorly developed lower slope and valley floor terraces. This appears to indicate that much of the local sheet wash material accumulates in the local stream channels and valley bottoms, although undoubtedly some is transferred out of the area and is involved in siltation of irrigation ditches, reservoirs, and paddy fields in the neighbouring lowlands. Quantitative support for this hypothesis is the actual siltation known to be occurring and the changing bed conditions of the Mai Ping above Chiang Mail In February 1979, during a brief visit to the area. farmers working the Mai Ping terraces a few km above Chiang Mai recited a graphic tale of changes in the hydrologic cycle of the mainstream over the last 20 to 30 years. This involved the description of what used to be farmable land 20 to 30 years ago as now completely under water during the peak summer monsoon discharge. What is more it is easy to wade across the Mai Ping during February-March-April, when 20 to 30 years ago the dry season discharge was much too great to permit wading.

FIG. 6. Three Schematic Slope Profiles, Showing Vegetation, Soil Losses, and Soil Pits

While these results are of a qualitative and somewhat speculative nature. they serve to reinforce the need, pointed out in the reports section of these proceedings, to undertake extensive soils mapping and soil erosion studies as part of the UNU additions to the original Huai Thung Choa Project.

Opportunities and Problems

The decision has been taken by UNU to utilize the preexisting Huai Thung Choa Highland Field Station and its ongoing forestry and horticultural research as a basis for a more broadly-based research and land-use applications programme embracing the UNU subprojects on Agro forestry and Highland-Lowland Interactive Systems. Many of the detailed recommendations are included elsewhere in these proceedings. Therefore, only a brief reiteration is made here.

First, training of Thai personnel at CATIE, Turrialba, Costa Rica, under Dr. Gerardo Budowski, will create an important opportunity to reinforce and ensure long-term continuation of agro-forestry research and applications into the Northern Thai mountains. A UN University-Chiang Mai University workshop focusing primarily on this topic is planned for November 1 979.

Next, the broadening of the project, to include soil and vegetation mapping, land-use mapping, micro-climatology, hydrology. and soil erosion studies, would seem to promise considerable benefits. But such benefits will only be fully achieved if the recommendations for socio-economic, anthropologic. and general human science research (as proposed by Kunstadter and Chapman, for instance: see relevant sections of these proceedings) can be carried out. All of these developments must recognize a number of organizational, educational, and practical problems. The more important of these are recognition that the Huai Thung Choa field area is not especially representative of the wider area of the Northern Thai Highlands: the need for integration of research to ensure a complementary human sciencesnatural sciences approach from the beginning; and the training of young Thai scientists and students in the concepts and practices of interdisciplinary team research. bearing in mind that the so-called industrialized and ''developed'' countries do not yet have very many complete successes to show in this area.

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