Stephen F. Siebert
Rattan, one of the world's most important non-wood forest products (NWFPs), vividly illustrates the difficulties and uncertainties inherent in ascertaining sustainable extraction levels and impacts associated with harvesting. Rattan is collected almost exclusively from wild populations and market demand for cane is strong. Indonesia supplies over 90% of the world's commercial rattan cane (Dransfield and Manokaran, 1993) and the majority is gathered from forests in which management has been largely absent or ineffective (Barr, 2000). There has been little or no monitoring or management of wild rattan harvesting and virtually nothing is known about ecological effects associated with extraction.
Sustainable harvesting of NWFPs has been advocated as a means to simultaneously conserve forests and encourage economic development (Anderson, 1990; Freese, 1997) and is now an integral component of most tropical forest conservation and management efforts (CIFOR, 1999). However, many ecologists contend that NWFP harvesting is neither ecologically sustainable nor economically viable (Kramer et al., 1997; Rice, et al., 1997) and that the notion of sustainable extraction is an ecological oxymoron (Struhsaker, 1998). Is sustainable wild rattan harvesting an oxymoron? If not, under what biophysical, socio-economic and institutional conditions might harvesting be viable? What methods could be employed to assess and monitor effects associated with cane extraction? Finally, if harvesting wild rattan results in adverse effects to other flora or fauna, how do those impacts compare with alternative economic activities (e.g., converting forests to annual or perennial cash crops)?
In this paper, I document opportunities and constraints to rattan cane harvesting, and methods to assess and monitor ecological effects associated with extraction. I focus on Calamus zollingeri, a commercially important large-diameter rattan used in furniture manufacturing, and base my analysis on five years of on-going research in Central Sulawesi, Indonesia. Given the wide range of possible direct and indirect ecological effects associated with harvesting in primary forests, I focus on only two of the most important: (i) direct impacts to the plant itself (i.e., to genets, ramets and ramet growth); and (ii) the use of floater logs to transport cane to market.
2. Calamus zollingeri Cane Harvesting and Monitoring Methods
Calamus zollingeri is a robust, clustering rattan found throughout Sulawesi, the Moluccas and other eastern Indonesia islands and is one of the most important large-diameter canes in the furniture industry (Dransfield and Manokaran, 1993). Virtually all C. zollingeri cane is collected from unmanaged, wild populations in primary forests. Despite prohibitions, huge quantities of C. zollingeri cane are collected from Lore Lindu National Park (LLNP) and cane harvesting shows no signs of declining (pers. obs.). Indeed, given the collapse of central Indonesian governmental authority to prohibit collecting and expanding export demand, rattan harvesting is likely to accelerate.
One of the challenges in assessing ecological sustainability is determining and establishing monitoring protocols for the vast array of possible direct and indirect biological effects. Principal effects associated with rattan cane harvesting at the species level include: effects to genets, ramets, and ramet production and growth; at the ecosystem level: effects on ecosystem nutrients, forest structure, forest succession, and vertebrate food resource availability; and indirect effects from transporting cane to market and incidental hunting of birds and mammals. While assertions by biologists that it is impossible to reliably and comprehensively ascertain all possible ecological effects is undoubtedly true, continued rattan harvesting necessitates that efforts be made to monitor and manage cane harvesting. Table 1 summarizes the primary direct and indirect effects associated with C. zollingeri cane harvesting in Central Sulawesi and the methods used to assess and monitor them in this study.
Table 1: Potential Effects of Rattan Cane Harvesting and Monitoring Methods
Genet population Structure
Cane (i.e. ramet) production
Resample permanently marked plants
Resample permanently marked plants and replicated sampling of random transects
" " " "
Forest succession and composition
Vertebrate food resources
Determine nutrients in foliage and canes and volume cane extracted/unit area
Long-term monitoring of sample plots
" " "
" " "
Biweekly sampling of marked plants
Not investigated in the study
Cane transport (floater logs)
Determine weight of rattan extracted, tree species and volume used as floater logs, and location trees extracted
Not investigated in this study
A wide variety of methods can be used to assess and monitor NWFP harvesting (Boot and Gullison, 1995; Godoy and Bawa, 1993; Hall and Bawa, 1993; Peters, 1994; Wong, 2000). I experimented with sample plots and transects of various sizes and lengths and found that the use of replicated belt transects measuring 10 x 500 m or 10 x 1000 m, randomly established perpendicular to the contour provided an effective, quick and easy way to assess and monitor C. zollingeri populations. Belt transects can also reliably sample the abundance and distribution of rattan and other lianas that tend to have patchy or clumped populations (Hegarty and Caballe, 1991).
I actively involved local rattan collectors in this project as key informants, research assistants, and in helping to identify important research questions and appropriate field sampling methods. Working with the same three experienced rattan collectors, we sampled an average of 500 m of transects per day. We sampled upslope in 10 m segments with two assistants recording the identity of all rattan species, the number of ramets/genet, cane lengths and evidence of harvesting within 5 m of either side of the transect line. We simultaneously gathered slope, elevation, light regime, soil, canopy height, and dominant tree species data along each transect (voucher specimens at the Herbarium, Tadulaku Univ., Palu, Sulawesi).
When first sampling the abundance and distribution of C. zollingeri in 1996, neither I nor my assistants knew how populations varied across the landscape or how they responded to site-specific environmental conditions (e.g., light and soil moisture). In the initial survey we found that C. zollingeri was restricted to lower montane forests below approximately 1150 m elevation. Consequently, we report C. zollingeri populations on a per hectare basis based on those portions of each transect below 1150 m. When recensusing the population in 2000, we sampled only forests below 1100 m using random transects of 10 m x 500 m length and again report the data on a per hectare basis.
To monitor potential harvesting effects on individual plants, we permanently marked (with flagging and metal tags) 106 mature C. zollingeri plants along the transects in 1996 and recorded the number of ramets, ramet lengths, evidence of cane harvesting and associated environmental conditions (as noted above). We also established three permanent 1 x 1 m sample plots around each plant to monitor the effects of cane harvesting on understory vegetation (i.e., extent and persistence of trampling). We resampled the marked plants and associated plots annually for four years. The field assistants monitored rattan flowering and fruiting phenology, and evidence of their use by birds and mammals on the marked plants on a biweekly basis for two years. We noted any evidence of damage to forest vegetation along the transects (i.e., branches broken or trees cut to harvest cane) each year and monitored their persistence for four years (e.g., natural and cut tree falls, trampling while harvesting cane).
Leaf and cane nutrient contents and losses associated with harvesting were assessed in paired leaf and cane samples (Siebert, 2001). Impacts of transporting cane to market were investigated by identifying the species, volume and location of trees harvested to float cane down river over a two-year period. Throughout the duration of this study, rattan (including marked plants) were harvested as desired by local collectors. In general, long canes (i.e., greater than 20 m) that could be readily pulled from supporting vegetation were preferred and no canes shorter than 10 m were cut. In the following sections I review only harvesting effects on C. zollingeri genets and ramets, and effects associated with transporting cane to market.
3. Ecological Effects Associated with Cane Harvesting
Calamus zollingeri is abundant and widely distributed throughout lower montane forests and is one of the most common rattans in and around LLNP. At approximately 1150 m it is replaced by Daemonorops sarasinorum and possibly C. sp "ahliduri", but all three species are marketed under the trade name "batang". We recorded an average of 149 C. zollingeri genets with 1431 ramets and 66 canes of harvestable length (i.e., > 10 m length) per hectare in forests below 1150 m when first sampling the case study watershed in 1996 (Table 2). In 2000 we found an average of 143 genets with 1595 ramets and 46 canes per hectare in the same watershed. Populations of C. zollingeri exhibited extremely patchy distribution with massive plants (i.e., greater than 20 ramets) dominating the understory and canopy along some portions of the transects, while no C. zollingeri were observed in other areas.
Table 2: Differences in Calamus zollingeri Genet and Ramet Populations over 4 Years
Mean number ha-1 (+/- std.dev.) based on 100 m2 sample plots along 3 random transects
1996 (n = 205)
2000 (n = 150)
149 (+/- 103)
143 (+/- 118)
1431 (+/- 1402)
1595 (+/- 1437)
(> 10 m)
66 (+/- 120)
46 (+/- 84)
Calamus zollingeri occurred in both high-light (e.g., canopy gaps) and densely-shaded environments, but was absent in poorly drained or seasonally flooded sites in both this site and a previous study in North Sulawesi (Siebert, 1993). Finally, we observed no evidence of mortality or dieback to C. zollingeri genets, irrespective of the frequency or number of canes harvested. For example, on marked plants we recorded no cane harvesting-induced mortality even though approximately 33% were harvested each year and in 2000 canes were frequently cut upon reaching 10 m in length.
On marked C. zollingeri plants we found that the mean number of ramets/genet was significantly greater in 2000 than in 1996 (Table 3). However, the mean number of harvestable ramets/genet (i.e., canes > 10 m length) was significantly lower in 2000 than in 1996, as was the mean length of harvestable cane and the total amount (i.e., length) of harvestable cane. In fact, in 2000 there was less than half the amount of harvestable cane as recorded on the same plants in 1996. The impact of intensive cane harvesting is readily apparent when comparing cane length distribution classes in 1996 with 2000 (Figure 1). For example, we recorded 37 canes greater than 20 m in length on marked C. zollingeri in 1996, but only three canes greater than 20 m on the same plants four years later.
Table 3: Calamus zollingeri Ramet Production and Growth over 4 Years on Marked Plants
Marked Plants (n = 74)
Mean number ramets/genet
Mean number harvestable ramets/genet (cane > 10 m)
Mean ramet (cane) length
Mean length harvestable ramet
(canes > 10 m)
Total length harvestable Cane (all plants)
** means significantly different at P=0.005 based on paired sample t test.
* means significantly different at P=0.05 based on paired sample t test.
These data have several important implications for the management of wild rattan. First, repeated cane harvesting (i.e., cutting mature ramets at approximately 1 m height) appears to stimulate the production of new ramets. Indeed, we recorded an average of 3.5 new ramets produced per genet and 4.7 m of cane growth on marked plants one year after harvesting. The production of new ramets and rapid cane growth suggests that large numbers of canes could continue to be available in the future. Secondly, cane harvesting has significantly reduced mean cane length which, in turn, reduces returns to labour and requires collectors to travel further into the forest. Thirdly, the cutting of all mature ramets may preclude sexual reproduction. This is supported by the absence of flowering and fruiting on marked rattan during two years of bi-weekly monitoring. While C. zollingeri is clearly capable of vigorous vegetative growth, sexual reproduction is important for maintaining species vigour and diversity over the long-term.
4. Effects of Cutting Trees for Use as Floater Logs
Transporting rattan to market in the southern LLNP region entails dragging rattan to a river, cutting and bundling cane, cutting small trees for floatation, and then floating the bundles down the Lariang River for 2-14 days to a roadside access point. The use of rivers to transport rattan, timber and other forest products is common throughout Asia. In the Lariang River drainage small trees are cut and dried to float rattan and tree cutting is reported to be a serious threat to biological diversity and forest conservation in LLNP (BCN, 1996; Schweithelm et al., 1992).
Eight tree species were regularly used to float rattan (Table 4). Not surprisingly, floater trees were light-weight, fast-growing, pioneer species. Floater logs averaged 25 cm diameter and 3 m in length, and typically floated a 50-60 kg bundle of cane. Canes were cut to 4 m length before bundling with the number of canes/bundle varying with cane diameter (i.e., weight). We recorded an average of 135 tons of rattan extracted each year from the case study watershed (from October 1996 to October 1998). If one conservatively assumes that each rattan bundle weighed 50 kg, a total of 2350 logs were required to float cane down river each year from the case study watershed.
Table 4: Tree Species Used to Float Rattan
Local Uma Name
Artocarpus teysmannii Miq.
Floater logs were harvested almost exclusively from fallowed shifting cultivation fields and to a lesser extent from naturally disturbed riparian flood plains along the Lariang River. Over the four-year study period, we found no evidence of floater log cutting in primary forests within LLNP. According to rattan collectors, floater logs are rarely harvested from primary forests because suitable-sized, light woods are uncommon there and because primary forests are further from the river than fallowed swiddens (pers. com.). Thus, there is little evidence to support the claim that cutting small, early successional trees to float cane threatens primary forests or biodiversity in LLNP, at least within this case study watershed.
5. Research Limitations and Future Research and Development Needs
The monitoring methods employed in this study, while time consuming and reasonably rigorous, are not comprehensive and certainly do not assess all possible ecological impacts associated with wild rattan harvesting. For example, we gathered no information on invertebrate use of C. zollingeri or hunting by rattan collectors. It should also be emphasized that we monitored C. zollingeri for only four years. Repeated harvesting of all mature cane could, over a long period of time, adversely affect plant vigour or ramet production and growth. Thus, as conservation biologists argue, we can not prove that C. zollingeri cane harvesting is ecologically sustainable or that it is without adverse ecological effects. Nevertheless, the use of randomized and replicated sampling methods over a four year period is biometrically rigorous (Wong, 2000) and can provide the basis for assessing ecological impacts and initiating adaptive management practices.
Given the absence of effective and enforceable prohibitions against rattan harvesting, the continuing devolution of Indonesian governmental power to provincial and local authorities, and growing development pressures in Indonesia and elsewhere in Southeast Asia, one must ask - how will resident people secure their livelihoods if rattan harvesting is prohibited? In Central Sulawesi, as in much of the tropical world, domestic and international market forces encourage the cultivation of export cash crops (e.g., oil palm, cacao, coffee, etc.) in large plantation schemes (Collier et al., 1994; Sunderlin, 1999). Under these conditions, if a forest has no value, it will likely be converted to something that does. When considered in this light, the potential ecological effects associated with C. zollingeri cane harvesting appear benign.
Comparing managed harvesting of wild rattan with agricultural plantations is also relevant because agriculture is the major cause of forest conversion in Southeast Asia and because the few large-scale efforts to cultivate and manage rattan have been on plantations (e.g., SAFODA, Malaysia). While long-term growth, yield and economic return data have not been published from these efforts, there is no agronomic reason why large-diameter, furniture-quality rattans could not be grown in large plantations. The long history of cultivating small and medium-sized rattan (C. caesius and C. trachycoleus) in swidden fallows in Kalimantan (Weinstock, 1983) suggests that large canes could be grown by small farmers as well.
This paper addresses ecological aspects of wild rattan gathering, a field in which I have expertise. However, even if harvesting wild rattan appears to be ecologically viable, socio-political and institutional aspects of cane extraction will require critical consideration. In addition, given declining wild rattan supplies it may prove necessary to cultivate rattan and that raises questions as to the type of production system one pursues. Key questions that policy makers must consider include: What is the most reliable and cost-efficient way of producing large-diameter rattan cane - management of wild populations or intensive cultivation by small farmers or in large plantations? What are the ecological effects associated with these different approaches? What economic costs and benefits are associated with managing wild populations vs. cultivating rattan in plantations? And what implications do these differing approaches have on the distribution of social and economic costs and benefits? In the following section I briefly review these issues in light of analyses by social scientists who have studied rattan and my own observations from Central Sulawesi.
6. Social, Economic and Institutional Challenges to Rattan Harvesting and Cultivation
Rattan is widely recognized as an important domestic and internationally-traded commodity. Indeed, rattan can be considered the "flagship" NWFP due to its unsurpassed importance in household, village, provincial and national economies. Rattan collection, trade, processing and manufacturing operate with a complex and dynamic socio-economic, political and ecological context. Crucial components include decentralized and dispersed cane collection; geographic centralization of manufacturing capacity; poor communications and infrastructure; ethnic, religious and social differences among collectors, traders and manufacturers; and the low priority of rattan among national governments.
Forests throughout Southeast Asia have been under formal state jurisdiction since colonial times, and both colonial and post-independence states have attempted to control and manage forest resources, albeit with great difficulty and limited success (Barr, 2000; Peluso, 1996; Sunderlin, 1999). In the case of rattan, efforts to control, regulate and manage cane harvesting have been largely absent or ineffective.
Since the 1970s, wild rattan supplies have drastically declined due to logging, forest conversion, over-harvesting, and forest fires. Some premier, large-diameter species such as C. manan, a solitary rattan that does not reproduce vegetatively, are nearly extinct (Dransfield and Manokaran, 1993 ). In some areas of Indonesia and elsewhere in Southeast Asia, rattan exploitation exemplifies what can occur under unregulated, open-access resource extraction conditions. However, in many regions the loss of rattan resources reflects political and economic choices by state and private industrial elites (backed by the military) to ignore traditional, customary resource tenure and forest management practices of resident ethnic minorities in the rush to exploit timber or convert forests to agricultural plantations. The "legal" destruction of wild and cultivated rattan for commercial logging and plantation agriculture is well documented among the Dayak of Kalimantan (Fried, 2000; Belsky, 1992) and has resulted in the destruction of traditional rattan production and management systems that have operated for generations. Studies by Mayer (1989), Dransfield (1988), Godoy and Feaw (1988), and Weinstock (1983) suggest that the social organization of small-holder rattan agroforestry systems were economically viable and reliably produced large quantities of cane in ways that were compatible with community economic and social well-being, and cultural identity (however, still not know if in a sustainable manner).
Given this history, is managed harvesting of wild rattan possible? If so, by whom and under what property rights arrangements? Given the success of smallholder rattan production systems, should they be protected, studied, used as models elsewhere? What are the comparative ecological, economic and socio-political benefits of smallholder vs. plantation rattan production systems? With regard to the latter, to what extent should concerns of ethnic minority cultural survival and economic justice enter into policy and resource development considerations?
Throughout Southeast Asia there is sufficient evidence to suggest that NWFPs, including rattan, have been successfully managed as a common property resource by traditional forest dwelling peoples for centuries (Lynch and Talbot, 1995; Peluso 1992; Peluso and Padoch 1996). In general, common property resource management succeeds where groups are relatively small and stable; where resource management perspectives, and issues of access and control are shared; and where enforcement is simple and inexpensive (Ostrom, 1990). However, historic common property resource management systems have been suppressed or usurped by colonial and post-colonial authorities in Indonesia and other Southeast Asian countries (Peluso, 1996). Consequently, the social and institutional characteristics required for communal management of wild rattan face tremendous challenges in many regions.
In Central Sulawesi rattan collecting is an important livelihood strategy for young men and for households unable to secure food and income through other, preferred means (e.g., irrigated rice farming, shifting cultivation and perennial cash crop farming). Indeed, half of the households interviewed in a random household survey conducted in 1999 reported that selling rattan was their most important source of income (coffee and cacao was the second most important source, cited by 30% of respondents). Rattan gathering is widely acknowledged to be dangerous and demanding work that involves extended periods away from home. Not surprisingly, once men are married or have producing coffee and cacao farms, they engage in rattan collection less often than before. Coffee and cacao begin to yield four and three years after planting, respectively. In contrast, large-diameter rattan will not likely produce cane in less than 12 to 15 years. Nevertheless, residents in this study area expressed interest in rattan cultivation and preliminary results indicate that C. zollingeri seedlings thrive when intercropped in shade-grown coffee and cacao farms (Siebert, 2000).
A narrow consideration of economic costs and benefits suggests that returns from rattan gathering and cultivation compare poorly with perennial cash crop alternatives. However, it is important to remember that rattan is a primary or secondary source of cash income for tens of thousands of forest-dwelling people throughout Southeast Asia (DeBeer and McDermott, 1989) and is an irreplaceable source of emergency income for thousands more (Siebert and Belsky, 1985). Furthermore, rattan gathering and cultivation by small-holders in either swidden fallows or as an intercrop in traditional agroforestry systems provides important social and environmental benefits that tend to be ignored in narrow cost/benefit analyses. Foremost among these benefits are: (i) reduced economic risk due to less dependence upon volatile coffee and cacao markets; (ii) the potential to increase total returns; (iii) reduced insect and disease infestation rates that may result from greater species and structural diversity; and (iv) the maintenance of high levels of biological diversity and thus at least partial compatibility with biodiversity conservation objectives.
Given the relatively low financial returns from wild rattan harvesting and long period of yield deferral when cultivating large-diameter canes, whether by small farmers or large estates, significant private investment in rattan management or cultivation is unlikely without outside (i.e., non-governmental, state or international) subsidies. Tayor and Zabin (2000) argue that support of community resource management such as this should be viewed not as a subsidy, but rather as payment for goods and services (e.g., carbon sequestration, functional watersheds, and biodiversity conservation) provided by intact forests. This approach could be broadened to include compensating people who are denied access to historic resources due to the establishment of protected areas. Targeted external funding of this sort could provide sufficient financial incentive for small farmers and rattan collectors to cultivate and manage rattan in and around protected areas. Increased returns from rattan harvesting might also be realized through green certification as advocated by the Rainforest Alliance and has been granted to timber harvested in certifiably sustainable ways.
Declining supplies and strong market demand suggest that rattan resources will become increasingly scarce, particularly for large-diameter canes. Two general approaches could be pursued to increase rattan supplies: management of wild populations and/or smallholder or estate cultivation. Both strategies entail significant challenges, particularly regarding the unfavourable financial returns (narrowly calculated) of rattan in comparison to cash crop alternatives. The two approaches will also have profoundly different effects on different sectors of society, particularly in the case of smallholder vs. estate cultivation.
I argue that efforts to manage wild rattan or to cultivate rattan in small farms or plantations should focus on: (i) large-diameter, furniture-quality, clustering species (i.e., those that produce multiple canes and sprout new ramets when cut); (ii) the establishment of rigorous and standardized monitoring protocols; and (iii) careful consideration of social and economic costs, benefits and their distribution among different sectors of society. Promising large-diameter, clustering and coppicing rattan species include C. zollingeri, C. merrillii and C. subinermis. Widespread adoption of rigorous and standardized monitoring methods will help elucidate long-term ecological and social effects associated with rattan harvesting and cultivation, and provide information that can be used to modify and adapt management systems within the context of dynamic, unpredictable and chaotic ecological, social, economic and political environments. Long term monitoring and adaptive management practices could also be used to benefit different segments of society. Careful attention to social justice and equity issues could help insure that those most dependent upon rattan resources benefit from future investments, while simultaneously reducing their need to convert protected and production forests to farms.
Successful rattan cultivation and management will require that local people participate in all aspects of the enterprise, not merely work as wage labourers. When people benefit from natural forests (e.g., managing wild rattan harvesting) or agricultural development (e.g., cultivating rattan), incentives can be created to retain forests and traditional, complex agroforestry practices, and the associated public goods and services that these systems provide (Western and Wright, 1994).
Managed harvesting of wild rattan and rattan cultivation will likely require significant long-term financial assistance, as well as technical and marketing support. It is essential that the size and type of support compliment local resource managers (i.e., resident people) and their institutional capabilities. Policy makers should pay particular attention to providing small farmers and rattan collectors with adequate economic incentives, particularly vis-à-vis perennial cash crop alternatives, and to developing secure, stable and enforceable resource management institutions and property rights. Private, state and international support for rattan management and cultivation can be justified as compensation for the public benefits provided by natural forests and diverse agroecosystems and for the loss of historic access to resources by forest dwellers living in and around protected and production forests.
I greatly appreciate the assistance, knowledge and friendship of Daud and Arnol from Moa, and the valuable comments provided by Jill Belsky on earlier drafts of this manuscript. This work was supported by USAID grant HRN-G-00-93-00047-00 and the University of Montana.
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