The Threatened Plants Unit & CPDU are reviewing Kew's Living Collection and identifying priorities for conservation management. Recovery plans are drafted in collaboration with botanic gardens and conservation agencies in countries of origin. Currently Kew has conservation programmes running for a number of species, selected examples are listed below:

• Abeliophyllum distichum
• Echium pinninana
• Sophora toromiro
• Tecophilaea cyanocrocus
• Draceana umbraculifera ( Bibliography )
• Mascarene Hyophorbe ( Bibliography )

The restricted geographical distribution and apparent rarity was commented upon by Cotton (1948):" Its distribution was confined to an exceedingly small area, and, had it not been brought into cultivation, it was not only a species but a genus which might easily have become extinct". Subsequently it has been the subject of a number of reports and studies (Yuan, 1974, Lee, 1976a, 1976b, 1990; Kim & Kim, 1990), however, no comprehensive study had been undertaken to identify the plants conservation status and management needs. A review of existing literature was undertaken followed by field surveys (Kim & Maunder, 1995). The study indicated that this species is declining in the wild and requires urgent management to reinstate regeneration in the surviving wild populations and to establish new wild populations.

Abeliophyllum is a monotypic genus closely allied to Forsythia but differing in having flattened broadly winged fruits in contrast with the capsular fruits of Forsythia. A number of colour forms have been identified from wild populations (Lee, 1976) with a pink form established in cultivation as the cultivar "Roseum".

The plant was first described in 1919 by Professor Takenoshin Nakai (1919) who originally collected it in the "Chinsen (sic Chinchon) Hills of Middle Korea" (Cotton, 1948). Seeds were sent to the Arnold Arboretum in 1924 by Mr T. Ishidoya (Wilson, 1928) and live plant material sent to Kew by Nakai in 1932. According to Cotton (1948) plants were also received in the 1930s by Lord Aberconway from the Arnold Arboretum. The species rapidly became established in cultivation with the Royal Horticultural Society awarding a Preliminary Commendation in 1936 to a plant from Lord Aberconway's collection, with a subsequent Award of Merit in 1937. A First Class Certificate was awarded in 1944 for sprays exhibited by J. Coutts of Woking. The plant was in the commercial trade by 1937 listed by the Keeper's Hill Nursery, Wimbourne, Dorset. The species has become a popular component of European (Kammeyer, 1972) and American gardens (Derbyshire, 1975). It has proved cold hardy and dependable in flowering, the species' naturally layering behaviour and ease of propagation by cuttings has ensured its adoption by the commercial nursery trade.

A review of existing literature followed by a survey in the spring of 1993 has established the distribution and status of the species in the Republic of Korea. Historically seven distinct localities have been recorded; all from the middle part of South Korean territory (Figure 1), with unconfirmed records from North Korea; three populations at the Koesan-gun area; one population at Mount Pukhan National Park discovered in 1973, by Yong No Lee & Yong Ja Oh, both Korean botanists, and Schneider, in the vicinity of the Seoul metropolitan area (Lee & Kil, 1991); one population at Yongdong-up, Chungchongpuk-do, discovered 1990; and, one locality in Puan-gun, Chollapuk-do, discovered 1992. The population recorded at Chinchon-gun has been subsequently extirpated (Natural Monument No. 14). Herbarium specimens in the Kyoto University (Lee,1987; Lee & Kil, 1991) indicate the existence of wild populations in North Korea collected by Japanese botanists, Koizumi and Saito in 1935, at Mt. Changsoo, Hwanghae-do, and by Japanese botanist, Saito at Nanam, Hamkyongnam-do. The population at Puan-gun has been partly destroyed by dam construction with several hundred rooted suckers translocated to a safe site in an adjacent valley during 1994 by the Department of Forest Resources, Chonpuk National University.

Abeliophyllum grows as an understorey shrub in mixed deciduous woodland, often under Pinus densiflora, Quercus myrsinaefolia and Q. acutissima. It forms a low growing and open thicket of suckering growths. In early spring before leaf break the white flowers of Abeliophyllum make a spectacular show against the russets and yellows of last seasons oak litter. Searches were undertaken during the flowering season when colonies where readily located. The precise ecological requirements of this species are difficult to judge however it is suspected that it thrives in the dappled shade of open deciduous woodland.

All the extant populations (except Yongdong-gun) are subject to intensive site management or have been translocated (e.g. Puan-gun). The management of sites entails fencing, in some cases pollarding of canopy trees (for instance at the Songdok-ni site), and the clearance of scrub amongst the Abeliophyllum plants (for instance at Chujom-ni site). In addition to well-meaning habitat management the species is threatened by visitor pressure (including off-road vehicles) and the illegal collection of plants. There is no reason to assume that any of these threats will diminish. The populations, whilst all protected by the National Monuments legislation, are under the management of a variety of authorities including private farms, national parks, country parks, university estates etc. The future of this species accordingly depends upon the identification and implementation of correct habitat management protocols across a number of differing land management agencies.

The ecology of the species requires study, there is little evidence of seedling recruitment in wild populations, this may be a result of overshading and competition. In addition preliminary studies of wild populations in Korea indicate very little seed set. Observations of cultivated material suggests that the species is self-incompatible requiring pollination between differing genotypes to ensure successful seed-set. Ongoing studies of genetics will assess the distribution of genetic diversity within and between populations. It is suspected that the wild populations are largely clonal colonies, accordingly there will be little production of seed. Ongoing morphological studies by one of the authors (YSK) indicates a wide variation in flower morphology amongst wild populations.

Abeliophyllum is cultivated in a number of Korean collections including the Chollipo Arboretum, Hantaek Botanic Garden, Keechungsan Botanic Garden, Kwanak Arboretum, Kwangnung Arboretum, and the Milim Botanic Garden (Anon., 1991). The majority of these cultivated stocks cannot be traced to any known provenance, however some collections do have stocks that are attributable through anecdote to the now extirpated population at Chinchon. One private collection cultivates samples from all known wild populations. It is known to be in cultivation in North Korea (Hwang, 1974). Only a few collections outside Korea cultivate documented wild origin accessions e.g. the Arnold Arboretum and RBG Kew. The cultivated stocks in North American and European arboreta and botanic gardens are largely clonal, and based on currently available information, duplicate both wild and cultivated genetic material in Korea.

Despite Cotton's fears (1948) Abeliophyllum has not become extinct, however, it is close to extinction and qualifies for the IUCN Category of "Critically Endangered", indicating a high risk of extinction in the near future. To ensure its survival as a wild species will require a revision of current habitat management procedures to encourage natural seed regeneration and the establishment of new and regenerating wild colonies. In parallel to this survey work will continue to search for new populations. In addition it is proposed that a field gene bank should be established in Korea to hold clonal samples from the wild populations. In addition such a facility could assess wild plants prior to developing new horticultural cultivars, notably larger flowered and good pink forms were observed in a number of wild populations. The conservation of this species in the wild is dependent upon an understanding of the regeneration ecology and the distribution of genetic diversity within and between populations.

Acknowledgements

This work could not have been undertaken without the support of the British Council in funding Professor Kim's research in the UK and Dr Mike Maunder's visit to Korea. Dr Stephen Spongberg of the Arnold Arboretum of Harvard University provided information on cultivated holdings of Abeliophyllum. The assistance of Dr Chong-Min Park, Chonpuk National University and Mr Carl Ferris Miller of the Chollipo Arboretum is gratefully acknowledged, their hospitality contributed greatly to the success and enjoyment of the field work undertaken in 1996.

References

• Anon., (1991) A Comprehensive Bibliography of Botanical Gardens in Korea. Korean Association of Botanical Gardens.
• Cotton, A.D. (1948) Abeliophyllum distichum. Curtis's Botanical Magazine 165:10
• Derbyshire, E. (1975) Shrub profile: Abeliophyllum distichum. Bull. Morris Arbor., 26(1):5.
• Hwang, H.H. (1974) Abeliophyllum distichum Nak., a shrub native to our country. Korean Nature 3(34):23-4.
• Kammeyer, H.F. (1972) Abeliophyllum, seltener Kleinstrauch unserer Gärten. Mitt. Deutsch. Dendrol. Ges., 64:132.
• Kim, Y.S. & Kim, T.W. (1990) The conservation of Korean rare and endangered plant species and the role of the botanic gardens and arboreta. Bulletin of the Kwanak Arboretum, Seoul National University 10:33-47.
• Kim, Y.S. & Maunder, M. (1995) A draft recovery plan for Abeliophyllum distichum. Unpublished report of the Yeungnam University and Royal Botanic Gardens, Kew.
• Lee, T.B. (1976a) Study on the conservation of endemic plant resources (Abeliophyllum distichum Nakai). Nature Preservation 12:6-10. (In Korean).
• Lee, T.B. (1976b) New forms of Abeliophyllum distichum. Journal of Korean Plant Taxonomy 7 (1-2):21-2. (In Korean).
• Lee, W.T. & Kil, B.S. (1991) The investigation of the natural growth region of Abeliophyllum distichum Nakai. Journal of Plant Taxonomy 2:1-8.
• Lee, Y.N. (1990) Abeliophyllum distichum Nakai. Association of Korean Nature Preservation Research Report 10:206-7. (In Korean).
• Wilson, E.H. (1928) Korean plants in gardens. The New Flora and Silva 1:10-1.

The Conservation Status of Echium pininana  By   Mike Maunder

The study species, Echium pininana, has been in cultivation for over eighty years and is widespread in cultivation within a number of distinct cultivated environments. It is likely that the cultivated population of E. pininana exceeds the wild population by an order of magnitude.

The study materials were derived from three sources (1) botanic garden stocks cultivated in glasshouses, (2) feral populations associated with botanic gardens in the UK and France, and (3) wild populations collected during field trips to La Palma, the Canary Islands.

Using inter-SSR primers the relative genetic architecture of wild, botanic gardens and feral populations were assessed. The resulting phenograms provide evidence for hybridisation within cultivated stocks. The results indicate that the three different stocks of Echium pininana differ in genetic status. The wild samples exhibit high levels of diversity relative to both the botanic garden and feral populations. It could be expected that the feral stocks with consistently larger effective population sizes could sustain a greater degree of variability than the numerically restricted botanic garden stocks. However the feral stocks exhibit a comparatively low level of infra-population diversity indicating a high degree of relatedness . It is suggested that the feral stocks are derived from botanic garden populations and have been subject to a population bottleneck prior to establishment as feral populations.
 

Conclusions

The molecular studies backed by anecdotal and archival studies indicates that the cultivated populations of E. pininana are a genetic sub-set of the wild populations. The largest proportion of the global population, the feral stocks, are in fact genetically depauperate relative to the wild populations. In addition the botanic garden stocks show evidence of hybridisation with related species. Accordingly the value of these extensive cultivated populations must be questioned.

The decline of E. pininana wild populations can be attributed to changes in the extent and quality of available habitat. The species survives as extensive soil seedbanks in the laurel forests, accordingly a large and diverse proportion of the total population can be released following appropriate habitat management. This would remove the need to import seed from botanic garden populations.

The value of this study to botanic garden studies is in the relative distribution of diversity between the different population types. It is suggested that cultivation in botanic gardens has dramatically reduced genetic diversity in E. pininana, when subsequently released into a high quality environment and with a logarithmic increase in population the plants still retain a low level of diversity. This provides a lesson for reintroductions, even for a widely cultivated botanic garden plant, the level of genetic diversity is reduced and the value of the stock further reduced through hybridisation. 

The Conservation status of the extinct Sophora toromiro from Rapa Nui (Easter Island)

If you require further information information on Sophora toromiro please visit the homepage of the Toromiro Management Group. 

The conservation status of Tecophilaea cyanocrocus

The plant was regarded as extinct in the wild from the 1950s onwards, attributed to over-collecting by bulb dealers, overgrazing by cattle ranchers and localised habitat change (per. comm. Alberto Bordeu, 1994). It is readily available from commercial dealers in the UK, Europe and North America. The material that was introduced into cultivation consisted of wild collected bulbs, which provided the original stock for the commercial trade. It has a reputation for being difficult to cultivate, as Farrer (1948) despaired: "No, no. Let salesmen say what they will, this glorious Gentian-blue Crocus from Chili is quite impossible of general cultivation in England". However, a number of private gardens established plantings from the original wild collections, these have persisted as self seeding and reproducing populations.

A plan to re-introduce this species has been drafted by RBG Kew and CONAF, Chile, with the support of the Alpine Garden Society. This is dependent upon a review of cultivated stock to assess genetic variation within a species that has been managed as a garden ornamental. CONAF are undertaking a review of the species old range with the aim of confirming it's status in the wild and identifying potential re-introduction sites. 

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