731. MAHONIA LINDSAYAE CANTAB Berberidaceae. James Cullen

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1 731. MAHONIA LINDSAYAE CANTAB Berberidaceae James Cullen Summary. Mahonia lindsayae P.F. Yeo Cantab is illustrated, and its history is revealed. This continues a series of articles on plants connected with the Botanic Garden of Cambridge University plants either raised there or distributed from there over the past 100 years or so. As with many of the others, this present plant has a complex history, involving accidental notice of seedlings and inferences about parentage; the original living plants have mostly disappeared, but descendants of some of them are still growing. The story behind this Mahonia begins with George Forrest s last ( ) expedition to China the one on which he himself died. Apparently somewhat against his will, he was accompanied by the American gardener Major Lawrence Johnston, who had founded two notable gardens in Europe Hidcote Manor in England and La Serre de la Madone near Mentone in France. Forrest was a difficult man in many ways, dedicated to exploration and collecting, and he found Johnston rather a troublesome companion. On arriving in Burma in November 1930, Forrest immediately began setting up the plans for the expedition hiring porters and equipment, and contacting his former native collectors in Yunnan. He was rather dismayed by the fact that Johnston spent his time either ill or socialising with the expatriate community in Rangoon and Bhamo, contributing very little to the planning of the expedition. Because Johnston was a financial contributor to the expedition as well as a participant, Forrest felt that he was in no position to complain. In fact, once Forrest was ready to set off, he found Johnston ill again and recommended that he (Johnston) return to Europe forthwith, while he himself travelled to Tengyueh (Tenchong), his usual base in southern Yunnan. In spite of Forrest s recommendation, Johnston later recovered and made the arduous journey across the mountains to Tenchong before Forrest had left there. Almost immediately he became ill again, and spent a long period restricted to the expedition s base. However, he did send out his bearer to obtain seed, and one of these collections was seed of the Curtis s Botanical Magazine 2012 vol. 29 (2): pp The Board of Trustees of the Royal Botanic Gardens, Kew 2012.

2 Plate 731 Mahonia lindsayae Cantab georita harriott

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4 plant then known as Mahonia lomariifolia Takeda - now considered to be M. oiwakensis Hayata subsp. lomariifolia (Takeda) J.M.H. Shaw, (see Shaw, 2011), described on the basis of an earlier collection by Forrest from hills north and east of Tengyueh, Forrest 9244, housed in the RBG Edinburgh herbarium (E). Forrest also collected the plant on his final expedition (Forrest 29056, also at Edinburgh), but the exact location for this is unknown, as, like many specimens collected on this expedition, it remained unlabelled at his death. By May 1931, Johnston was so ill that he decided to return to Europe, leaving Forrest to continue his collecting. (More detail about Johnston s participation in the Forrest expedition is given in McLean s excellent biography of Forrest (McLean, 2004) and Pearson (2010) essentially corroborates these details). On his return, seeds of the plant collected as Mahonia lomariifolia were sown at La Serre de la Madone, and germinated. Much to Johnston s surprise, plants of two distinctly different kinds appeared in the pots; these were separated out and both grown on. As time went on, it became clear that some of the plants were indeed what they were supposed to be (M. lomariifolia), whereas the others were quite distinct (lomariifolia has numerous, rather narrow leaflets and stiffly upright secund racemes, whereas these other plants had fewer, broader leaflets with distinct yellowish venation above, and more arching, less secund racemes). Johston referred informally to these new plants as yunnanensis. They continued to grow and flower spectacularly at La Serre, without any further research being devoted to them. It is quite easy to understand how a non-experienced collector could have collected fruit from two adjacent plants thinking that they were all from the same plant. In 1948, Johnston moved finally to La Serre, and gifted the house and garden at Hidcote to the National Trust, with Miss Nancy Lindsay, the daughter of his friend and landscape architect, Peter Lindsay, as his...memory and shadow while away (Pearson, 2010: 234). An uneasy relationship continued between Miss Lindsay and the Trust, but most issues were finally resolved. Johnston continued to rely on Miss Lindsay, and at his death in 1958, she inherited the garden at La Serre. Almost immediately on inheriting the garden, Miss Lindsay invited Mr John Gilmour (then Director of the Cambridge University Botanic The Board of Trustees of the Royal Botanic Gardens, Kew

5 Garden) and Mr Bob Younger (Superintendent) to visit and to take material of any plants they thought might be interesting (Gilmour, 1963). One such plant was the yunnanensis Mahonia, of which three plants were still growing. Gilmour and Younger took back the smallest of these, and grew it on in the Temperate House at the Cambridge Botanic Garden where it flowered for the first time in Other material (from seedlings under the original plant and cuttings from it) was also acquired; much of this was grown outof-doors in Cambridge, and soon died off. Gilmour sent flowering material of the temperate plant house to Kew for identification, and it was determined as M. siamensis Takeda by Robert Sealy. This was a reasonable identification in terms of the literature (mainly Takeda s revision of 1917), and specimens available at Kew, but it did raise a problem: M. siamensis was known only from Doi Sutep in northern Thailand, some 350 miles distant from the place where Johnston s plant was collected. The rather curious disjunct distribution so created was puzzling, but the identification was accepted, and the Cambridge plant (from the temperate house) was treated in this Magazine as n.s. plate 605, beautifully painted by Margaret Stones and with a text by Dr P. F. Yeo (1972b), the taxonomist at Cambridge University Botanic Garden. Yeo commented on the disjunction but offered no explanation. In fact this problem was not resolved until the recent publication of Mahonia in the Flora of China vol. 19, (Ying & Chen, 2001), where M. siamensis is treated as a synonym of M. duclouxiana Gagnepain, a species originally described from southern Yunnan (China), not known to Takeda when he wrote his paper, but treated by the Flora s authors as widespread in India, Burma, southern China, Vietnam and northern Thailand, thus eliminating the apparent disjunction. Plate 605 should therefore be considered to be M. duclouxiana. Very few specimens from this original introduction (under the name siamensis) appear to have survived in gardens. But Mr Glyn Jones, Head Gardener at Hidcote and Mr Martin Smith (Head Gardener at La Serre de la Madone) tell me that the original plant is still growing at La Serre, see Fig. 1...though in a part of the garden that is relatively inaccessible. Mr Smith has sent me photographs of the plant taken from some distance. Further, Mr Steve Protheroe, Specialist Garden Manager at Swansea Botanic Complex, reports that there is a plant growing 126 The Board of Trustees of the Royal Botanic Gardens, Kew 2012.

6 Fig. 1. The original plant of M. siamensis (i.e. M. duclouxiana) at Serre de la Madone. Photograph: M. Smith, February under the name siamensis in Singleton Botanic Park in Swansea. This plant was photographed in 2005 and the photo is available on the web ( a64.jpg). Finally, Dr Tom Daniel of the The Board of Trustees of the Royal Botanic Gardens, Kew

7 Department of Botany, California Academy of Sciences and Director of the Stanley Smith (US) Horticultural Trust, reports that a plant has been grown in the Strybing Arboretum, Golden Gate Park, San Francisco for many years under the name M. siamensis. Recently, this has been re-named as M. duclouxiana. A photograph of this is also on the web (www. flickr.com 4859d6aabb.jpg). In so far as identifications of photographs can be accurately made, I am satisfied that all these photographs represent the plant in question and must derive from the original, single introduction of M. siamensis. All this history and confusion (which re-inforces Lancaster s comment (2009) that the taxonomy, and therefore the nomenclature of Chinese Mahonias are not for the faint-hearted ) is preliminary to the origin of M. lindsayae. This is described by Yeo (1972a): one of the seedlings from La Serre was planted under the larger siamensis in the Cambridge temperate house. Yeo noticed this seedling in flower in 1964, and...immediately saw that it was not identical to the specimen that had been brought from France as a plant. Careful consideration of this plant by Yeo showed that...in numerous characters it was half-way intermediate between M. siamensis [i.e. M. duclouxiana] and M. japonica. The plant was provisionally assumed to be a hybrid between these two species, and to have arisen from a chance cross-pollination that must have taken place at the Serre de la Madone. I thereupon pollinated flowers of M. siamensis with pollen from M. japonica but no viable seed was obtained. However, M. siamensis set no seed when pollinated with itself, and the hybrid set no good seed when crossed with either parent. Therefore, although the negative results of the interspecific cross need not be regarded as a serious objection to my theory, it did mean that no plants of M. japonica M. siamensis of certified parentage could be raised. However, I see no reason to doubt my first diagnosis of the origin of the seedling. On the basis of all the information before me, I agree with Yeo s diagnosis, and have been much helped in this because Yeo was meticulous in making herbarium specimens of all the material he dealt with, and these (including the type specimen) remain in the Botanic Garden s herbarium (CGG) where they are available for study and comparison. The suggested parentage still remains an inference, and 128 The Board of Trustees of the Royal Botanic Gardens, Kew 2012.

8 is not derived from direct evidence; plants of the hybrid combine characters of the two parents rather than being intermediate between them. A comparison of the important characters in the hybrid and its presumed parental species is given in Table 1. The fragrance of the flowers of Mahonia lindsayae is somewhat problematic. Yeo (1972a) writes: The strong scent seems to be a blend of the hyacinth of M. siamensis and the lily-of-the-valley of M. japonica. I have been unable to confirm this: to me (and this is also the experience of the artist, Georita Harriott, who has kept inflorescences by her for some considerable periods), the flowers of the hybrid have a very faint and fugitive honey scent, while those of M. japonica have a much stronger and persistent honey scent. It is possible that the cold and generally windy weather of January and February 2012 have contributed to this discrepancy. In his publication (1972a), Yeo described the hybrid as M. lindsayi Cantab and explained that the collective epithet (lindsayi) commemorated Miss Lindsay. However, this being the case, the collective epithet should have been spelled lindsayae (feminine, to agree with Miss Lindsay), and this indeed is the spelling used by Yeo on all the herbarium specimen labels. Why he used the spelling with an I in his publication is completely obscure (I am grateful to Dr R. K. Brummitt for help over this general point). Before describing the plant and its differences from its (putative) parents, it is necessary to comment on the morphology of the leaves of the taxa dealt with here (much of this comment applies to many of the species of the genus). The leaves are imparipinnate with opposite leaflets; at the base of the leaf, just above the node, there is, in most Asiatic species, a pair of leaflets which are generally smaller, rounder and less spiny-margined than the others. These are generally very stipule-like in size and position (though they don t, as far as I have seen, join on to the stem at all), and are referred to as stipules in some of the literature, though I have not found any definite information about this many books describe the family Berberidaceae as usually without stipules or use some similar wording. These leaflets are discussed in Ahrendt (1961: 7 8). They are important taxonomically in that the length of rachis (leaflet-internode) between them and the next pair of leaflets is variable; in some species this length is much greater than that between the pairs of leaflets above, in others it is The Board of Trustees of the Royal Botanic Gardens, Kew

9 Table 1. Characters of M. lindsayae and its presumed parents. japonica lindsayae duclouxiana Habit More or less erect Arching over Erect, widely branched Mature bark Scarcely fluted, not corky (fig. 5) Deeply fluted, corky Deeply fluted, corky (fig. 4) (fig. 3) Leaflets Leaflet venation above Not prominent or pale greenish Prominent, pale greenish yellow Prominent, pale greenish yellow yellow Internode above Equalling other internodes Conspicuously longer than others Conspicuously longer than others lowermost leaflets Racemes Greenish yellow in bud; spreading, then curving upwards, somewhat secund, with about 100 flowers; unbranched; sterile base with several small ovate bracts Fertile bracts Narrowly ovate, acute, to 7 mm, almost as long as pedicels Yellow in bud; spreading, then arching upwards, somewhat secund, with flowers; some with lateral racemes at base; sterile base with 1 or 2 linear bracts Linear, 1 2 mm, much shorter than pedicels (which are ca. 6 mm) Red-tinged in bud; slightly arching to erect, scarcely secund, with many more than 100 flowers; most with lateral racemes at base; sterile base with 1 or 2 linear bracts Linear, shorter than pedicels (which are ca mm) Flower buds Green, pruinose Yellowish, not pruinose Yellowish, not pruinose Outer 3 perianth-segments ca. 5 mm, green in bud, greenish in flower 2 4 mm, yellow with reddish lines mm, yellow flushed red at base 130 The Board of Trustees of the Royal Botanic Gardens, Kew 2012.

10 Fig. 2. Mahonia lindsayae Cantab. A, leaf rachis showing joint, 1; B, leaf rachis showing attachment of leaflet, 1; C, flower, side view, 3; D. flower, side view, showing stamens and ovary, 3; E, innermost perianth segment with stamen, 3; F, inner perianth segment, 3; G, exterior sepal, 3; H, apex of stamen, showing anther, 10; J, interior sepal (1 of 3 similar), 3; K, T.S. ovary, 4; L, apex of ovary, showing stigma, 6. Drawn by Georita Harriott from specimens at the University Botanic Garden, Cambridge. about the same. This part of the rachis is not a petiole as such, unless the lowermost pair of leaflets are considered to be stipules, and should not be confused with the genuine petiole found in such species as the widely cultivated M. aquifolium (Pursh) Nuttall. A further peculiarity of the leaf-rachis in these species and most of the others that I have looked at, is that the rachis is jointed at each pair of leaflets; further, the leaflets, when sessile, as they are in the species dealt with here, are also jointed to the rachis (see Fig. 2). The significance of this characteristic is uncertain. Cultivation. Mahonia lindsayae is generally easily cultivated, requiring conditions suitable for the much more commonly grown M. japonica. Generally speaking, open woodland conditions are best, The Board of Trustees of the Royal Botanic Gardens, Kew

11 allowing the plant some space; it will tolerate quite dense shade, but will not flower so well under these conditions. As regards propagation, my colleague Peter Kerley, who has propagated the plant several times reports: At Cambridge we have obtained good success by inserting cuttings into free-draining compost and placing them in a mist unit in February, or under bottom heat in early October. The single-node cuttings need to consist of a bud, a single leaf and a piece of stem about 2.5 cm long from the previous season s growth. The length of the leaf can be reduced to two pairs of leaflets for convenience. A high proportion of the cuttings can be expected to root in 8 10 weeks. Mahonia lindsayae P. F. Yeo, Journ. Roy. Hort. Soc. 97: (1972). Thought to be M. duclouxiana Gagnepain (M. siamensis Takeda) M. japonica (Thunb.) DC. Description. Shrub with yellow wood, branched at the base, the stems more or less erect but arching over above, to 2 m (or more?). Bark pale brown, deeply channelled with five to seven grooves with corky ridges between them (see Fig. 3). Leaves crowded towards the branch-apices, evergreen, imparipinnate with leaflets and a pair of smaller, stipule-like leaflets at the base, to 35 cm. Rachis reddish-brown above, jointed at each leaflet-node. Stipule-like leaflets borne on the rachis just above its insertion on the stem, ovate or broadly elliptic, smaller and less spiny than, but otherwise similar to the main leaflets; length of rachis between the stipule-like leaflets and the first pair of main leaflets is 8 14 cm, considerably longer than the lengths of rachis between subsequent leaflet-pairs. Main leaflets cm, dark green with venation conspicuous, pale greenish yellow above, pale green beneath, obliquely inserted and jointed on to the rachis, narrowly oblong-ovate, margins with 4 6 teeth per side, each tooth ending in a short, sharp, brownish spine. Inflorescence a whorl of racemes borne at the apices of the stems; racemes 4 8 arising from the axils of the leaves, spreading widely and sometimes arching upwards towards the apex, cm with about 60 flowers, somewhat secund, some of them with a small flowering branch at the base; the base of the racemestalk bears 1 3 small, sterile, linear bracts. Fertile bracts greenish, 1 2 mm, much shorter than the pedicels (which are ca. 6 mm). Outermost perianth-segments forming a whorl of three, each ovate, mm, yellow (even in bud), with reddish longitudinal lines; within these are two whorls of three segments each which spread widely; these are all yellow, obovate, those of the outer of the two whorls ca. 6 4 mm, those of the inner whorl ca mm. Finally, within these are six innermost perianth segments which are not obviously in two whorls; these are yellow ca. 8 mm, and have more or less erect bases forming a cup and spreading apices which are rather obscurely notched; a stamen (ca. 6 mm) is loosely attached to each of these, and at the sides of the stamen-attachment are two nectaries, which are very difficult to see (they are 132 The Board of Trustees of the Royal Botanic Gardens, Kew 2012.

12 Fig. 3. Bark of Mahonia lindsayae in Cambridge University Botanic Garden. Photograph: P. J. Atkinson. slightly raised and slightly darker in colour than the rest of the segment). The anthers open by valves which fold upwards, and the apex of the connective is slightly pointed. Ovary is ovoid with 2 3 ovules; style 1 2 mm. Fruit ovoid, The Board of Trustees of the Royal Botanic Gardens, Kew

13 Fig. 4. Bark of Mahonia duclouxiana in Strybing Arboretum, California. Photograph: T. F. Daniel. 134 The Board of Trustees of the Royal Botanic Gardens, Kew 2012.

14 Fig. 5. Bark of Mahonia japonica in Cambridge University Botanic Garden. Photograph P. J. Atkinson. dark bluish purple and pruinose, containing 2 3 seeds which appear to be non-viable. Distribution. Garden origin. Flowering time. December to March. The Board of Trustees of the Royal Botanic Gardens, Kew

15 Acknowledgements. I would like to acknowledge the help of Suzanne Cubey (RBG Edinburgh) for help with details of relevant herbarium specimens collected by George Forrest; Peter Atkinson of Cambridge University Botanic Garden for photographs of the bark of relevant plants, Dr T. Daniel of the Department of Botany, California Academy of Sciences for information about plants in the Strybing Arboretum and for the photograph of the bark of M. duclouxiana, and Mr Glyn Jones (Hidcote) & Mr Martin Smith (La Serre de la Madone) for photographs and other information. REFERENCES Ahrendt, L.W.A. (1961). Berberis and Mahonia. A taxonomic revision. Journal of the Linnean Society (Botany) 57: Gilmour, J.S.L. (1963). Notes from fellows: Mahonia siamensis. Journal of the Royal Horticultural Society 88: 129. Lancaster, R. (2009). New Chinese Mahonia in British cultivation. The Plantsman (New Series) 8: McLean, B. (2004). George Forrest, Plant Hunter. Antique Collector s Club, Woodbridge. Pearson, G.S. (2010). Lawrence Johnston, Creator of Hidcote. Hidcote Books, Chipping Camden. Shaw, J.M.H. (2011). Developments in Mahonia. The Plantsman (New Series) 10: Takeda, H. (1917). Contributions to the knowledge of the Old World species of the genus Mahonia. Notes from the Royal Botanic Garden, Edinburgh 6: Yeo, P.F. (1972a). A hybrid of Mahonia siamensis. Journal of the Royal Horticultural Society 97: Yeo, P.F. (1972b). Mahonia siamensis. Curtis s Botanical Magazine 175: t Ying, T. & Chen, D. (2001). Berberidaceae. In: English translation edited by Boufford, D.E. & Brach, A.R. (eds) Flora Reipublicae Popularis Sinicae. Vol. 19. pp Accessed The Board of Trustees of the Royal Botanic Gardens, Kew 2012.