Over-exploitation is among the greatest threats to the survival of plant species. Theoretically, reduction of wild harvesting pressure can be dealt with from the supply side and/or the consumer side. Supply-side conservation interventions include measures to increase supply from non-wild harvested sources (i.e., through cultivation). This intervention is appealing because it also has the potential to alleviate rural poverty.
In practice, however, commercial cultivations have rarely been shown to alleviate wild harvest pressure for a variety reasons. One major reason is that cultivated products are not complete substitutes for wild collected ones. For example, certain wild-collected medicinal herbs are deemed more potent and of higher quality, and enjoy a price premium. In addition, some herbal medicinal plants growing in industrial shade houses are subject to synthetic fertilizers and pesticides, which indeed make the cultivated product less desirable. The deeply entrenched belief that wild plants are superior as a Traditional Chinese Medicine source also makes the consumer-side interventions ineffective.
We currently focus on understanding the efficacy of semi-wild cultivation as a conservation measure for Chinese wild orchids and American ginseng, both of which are endangered and used as traditional homeopathic medicine. In general terms, semi-wild cultivation refers to plantations located in the target species' native range and habitats.
For conservation of Chinese wild orchids, we have carried out projects to understand the nature of wild orchid trade in China, and tie this knowledge with the Chinese orchids Redlisting assessment. We also lead an effort to establish a dynamic national wild orchid trade list to be used in future orchid redlist assessments. In the meantime, we are quantifying the benefits of semi-wild cultivation of medicinal orchids on nature conservation and poverty alleviation.
Demand for wild-harvest American ginseng (Panax quinquefolius) - a well-known medicinal herb native to the deciduous forests in the Eastern United States - persists despite mature large-scale shadehouse cultivation. We are starting an effort to quantify the benefit of semi-wild cultivation of American ginseng and explore ways to use this understanding for marketing among the global East Asian communities, the main consumer group of the species.
We believe that thoughtful implementation of semi-wild cultivation can be a key in solving the wicked conservation issues facing plants with high economic and social values. It can promote sustainable use because it has the potential to satisfy the market demand for wild-sourced products and create wealth for local farmers, while contributing to the stability of wild populations. However, to what extent these two functions can be realized and under what social and ecological conditions is unclear. Our research will help to gain this understanding.
For more information on this project, contact Hong Liu.