Nature

Bright prospects for the magnolia

The magnolia is one of many medicinally valuable plants threatened by logging, intensive farming and over-harvesting in China. But the country's radical new plant conservation strategy may turn this around. James Wong reports.

When the infamous plant hunter Ernest Henry Wilson trekked across China’s western mountains in 1904, he reported a profusion of pure white Magnolias growing amid the scrub, moist woodland and open fields. Yet a century on, the voluptuous pendant flowers and medicinal bark of Wilson’s White Magnolia (Magnolia wilsonii) are rarely seen even by the most adept local, highlighting the ecological and healthcare issues facing the region.

The main problem we have is finding the tree nowadays,” says Wen Xiang Ling, a traditional healer from Yunnan Province, “when I was a girl this grew plentifully near our village, but each year we have to go higher into the mountains to find it.” The bark, harvested from the branches, leaves and roots, is an important part of traditional local medicine and has been demonstrated to have powerful anti-anxiety and anti-angiogenic properties, as well as being useful in reducing allergic and asthmatic reactions.

Clear-cut logging, the spread of intensive farming and the continuing over-harvesting for the bark itself, have taken their toll on these trees, which are now confined to a few small scattered populations in the provinces of Sichuan, northern Yunnan and Guizhou. However, clinging to the steepest slopes of the mountains of western China, new hope is emerging for Wilson’s White Magnolia.

Coming in the face of what scientists are calling a “burgeoning ecological crisis”, this year China is launching a radical new “National Strategy for Plant Conservation”. Representing the country’s first ever coordinated, country-level response, the strategy aims to halt China’s continuing loss of plant diversity, helping safeguard the future of some 5,000 threatened plant species.

The launch of this plan couldn’t be more timely,” said Sara Oldfield, secretary general of charity Botanic Gardens Conservation International (BGCI), who proved key in initiating the strategy. “With the number of threatened Chinese plant species leaping an astonishing tenfold in the 12 years between 1992 and 2004, and some 20% of China’s flora now considered at risk, now is the time to act to save plants like Wilson’s White Magnolia.”

With the repercussions of this ecological crisis increasingly visible on China’s landscape, this strategy is far more than just political "green-wash." Its ambitious plan reflects a deep, multi-million dollar commitment to the importance of the country’s rich native flora – one of the top three most biodiverse on earth. The mammoth project tackles the root causes of the nation’s species loss, using a combination of tough legislation, massive investment in practical plant conservation measures and the development of a state-wide environmental education scheme.

The plan offers hope to China’s thousands of threatened plant species like Wilson’s White Magnolia. It calls for a complete halt to logging over vast stretches of forest in the upper reaches of the Yangtze River and Yellow River, where the last remnant populations of the tree are found. In one step, this could relieve the single greatest pressure facing the Magnolia’s survival. And the plan will be backed up by strict enforcement measures, which will include an “aggressive crackdown on illegal logging and plant harvesting nationwide.”

China has also announced a ban on “all potentially polluting development projects near key areas of biodiversity,” as well as plans to revert nearly 15 million hectares of farmland to forest in the next three years, an area of land bigger than the whole of England. Interestingly, many of the species used in these reforestation schemes are expected to include native and threatened trees, such as Magnolia wilsonii, expanding their native range across huge swathes of the country.

Recognising the importance and potentially lucrative income to be gained from the country's native medicinal plants, China is also setting up large medicinal plant cultivation projects. In addition to taking pressure off wild populations of plants such as Wilson’s White Magnolia, the projects will also act as "gene banks" to regenerate genetic diversity in these species, and research their applications in modern medicine.

The strategy also calls for stepping up investment in botanic gardens, an important refuge for the genetic diversity of Magnolia wilsonii. Just 14 of China's botanic gardens already contain specimens of two-thirds of the country's total flora.

These goals will bring China into line with the internationally-agreed targets of the "Global Strategy for Plant Conservation", adopted by over 180 countries that are signatories of the Convention on Biological Diversity, but they are said to be adapted to the particular Chinese context. 

Says Oldfield: “China’s great enthusiasm and commitment in developing this strategy is extremely positive news for plant conservation efforts globally. We are delighted to have been involved in this historic move and, with our garden members, will be working hard to support China’s Strategy for Plant Conservation.”

Homepage photo by autan

James Wong is a Kew-trained ethnobotanist and works for Botanic Gardens Conservation International, the world’s largest plant conservation network. He has written for a number of publications, from the BBC to the Kitchen Gardener Magazine, on a wide range of botanical topics.