Since their discovery, two Nepalese have either been regarded as the same , or been confused, by botanists and gardeners. Tony Schilling and Mark Watson conclude that they are distinct and show how to separate them.

Clarifying the identities

hree species of and why the confusion came about early 19th century, based on are reported as native to initially and has persisted for so long. herbarium specimens collected by TNepal (Press et al. 2000): Following an examination of living Francis Buchanan-Hamilton (in Mark Flanagan M. acanthifolia G. Don, M. borealis and herbarium material of Nepalese 1802; see Boufford 2013) and Takeda and M. napaulensis DC. Both Mahonia, combined with our own Nathaniel Wallich (in 1818–1821) M. acanthifolia and M. napaulensis field observations, we here attempt respectively. The latter included have been in cultivation in Western to resolve this confusion. material sent to Wallich by Edward gardens since the middle of the 19th The Nepalese records of M. borealis, Gardner, the first British Resident century. However, despite the a northwest Himalayan species, have (ambassador) in Kathmandu. passing of nearly 200 years since been re-examined and are now con­ Mahonia napaulensis was the first they were described, the separate sidered to be misidentifications of to be described (in 1821) by the Swiss identity and synonymy of these two M. acanthifolia, and so we recognize botanist Augustin de Candolle using taxa continue to be debated. only two species of Mahonia in . material gathered by Buchanan- In our opinion, these two Hamilton in the Kathmandu Valley. Nepalese species are clearly distinct Early taxonomic history It has leaves bearing six pairs of and readily separated, so much so Both M. acanthifolia and similarly sized leaflets and a smaller that it is difficult to understand how M. napaulensis were described in the pair of lower leaflets inserted close to

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of two Nepalese Mahonia

Mark Watson Mahonia napaulensis (left) has significantly fewer Making taxonomic decisions based Joseph Hooker studied Mahonia leaflets per leaf thanM. acanthifolia (above) on limited or inadequate collections in and Darjeeling in the late was clearly a problem then, and 1840s, and concluded that these two the base of the leaf (often appearing continues to be so today. Mahonias species should be united under the like stipules). are large, spiky shrubs that have earlier name of M. napaulensis Ten years later George Don tended to be avoided by collectors of (Hooker & Thomson 1855). They described M. acanthifolia. He took herbarium specimens. Furthermore, adopted a very broad species concept, up a manuscript name of Wallich, it is difficult to represent the variation writing ‘we have no hesitation in written on original labels on two seen in a large Mahonia on a uniting the Peninsular and Khasia specimens in the East single herbarium sheet and so early with the Himalayan species, not­ Company Herbarium, now at Royal collections can be difficult to withstanding the difference in shape Botanic Gardens, Kew (herbarium interpret. However, by combining of the berries and leaflets between code K-W). He described it as a studies in the herbarium with the extreme states of each. Dr larger shrub with a greater number of observations taken from living Wight informs us that he has culti­ leaflet pairs, he thought up to 10. But in the field and in cultivation, we vated the Himalayan one side by side Don commented that it might be have come to a better understanding in his garden with that of the the same as M. napaulensis. of the delimitation of these species. Nilghiri, and finds them to be ➤

June 2014 95 indistinguishable. Specimens of the Fruit collecting in Sikkim. In contrast to shrubby Sikkim plant, cultivated for a good M. napaulensis, M. acanthifolia eventually forms a plant that is sturdy enough to climb many years at Dorjiling [Darjeeling], acquired longer racemes, larger flowers, and more slender pedicels from the Kathmandu Valley. Takeda than the wild specimens in the referred all the other Mahonia in adjacent woods. The are very Nepal to M. acanthifolia, a species variable organs.’ with leaves of up to 11 pairs of This early use of comparing plants leaflets, and geographically much in the wild and in cultivation is more widely spread, from northwest notable, but it is not clear if material Himalaya to east Himalaya and of M. napaulensis (in our narrow northeast India. He commented sense) from the Kathmandu Valley that ‘among the Indian species was included in these experiments. M. acanthifolia can easily be The Mahonia grown at the Calcutta distinguished by having very small Botanical Garden (‘Berberis pinnata outermost [enclosing the Roxb.’, listed in the 1814 garden flower in bud], apiculate-triangular catalogue Hortus Bengalensis), was connective, and large luxuriant leaf collected by MR Smith from with numerous leaflets which are Manipur, northeast India, and so furnished with a few large teeth.’ could not have been M. napaulensis Leslie Ahrendt (1961) published as we now understand it, and was the most recent comprehensive Brian Mathew presumably M. manipurensis Takeda. monographic treatment of Mahonia in his global revision of both Berberis the Indian species, including the First monographs and Mahonia. Ahrendt agreed with south Indian M. leschenaultii (Wight At the end of the 19th century and Takeda and increased the distinction & Arn.) Tanaka ex Dunn and the first half of the 20th century there between M. napaulensis and northeast Indian M. manipurensis, was an increase in botanical M. acanthifolia by placing them in within M. napaulensis. exploration of Asia, and the first separate subsections. He highlighted monographic treatment of Old the very short, ‘insignificant’ style of Recent studies World Mahonia by Friedrich Fedde M. napaulensis as another useful Boufford (2013) recently commented: (1901). Fedde followed Hooker & distinction, as compared with the ‘the wide variation in leaf and leaflet Thomson, including M. acanthifolia 1mm style of M. acanthifolia. morphology in Mahonia napaulensis within M. napaulensis. Himalayan floristic works contin­ [in the wide sense] makes it easy to Takeda (1917) took a fresh look at ued to follow this separation of the understand why so many names have the Indian species, commenting that Nepalese species until the Flora of been applied to this complex and since Hooker and Thomson ‘unhesi­ in which Grierson (1984) felt wide-ranging species. In the flowers tatingly united all Indian species … that available herbarium material and fruits and in the structure of the into a single species, M. napaulensis, was too scanty to differentiate , however, there is … almost all the later workers have between the east Himalayan species remarkably little variation. And, indiscriminately followed this reliably. Grierson concluded that when large numbers of specimens opinion.’ Takeda set out ‘to ascertain ‘until the genus is better collected it are examined the variation in the the real M. napaulensis’, concluding seems preferable to regard Mahonia leaves can be seen to be continuous that this species had never been as being represented in this area by a and not warranting taxonomic found outside Nepal, and that single species’. The illustration recognition.’ We agree that the previous authors were misguided. provided in the Flora is reminiscent variation seen in dried material Takeda reported that the leaves of of M. napaulensis, in the narrow sense, makes it difficult to delimit species M. napaulensis had 3–7 pairs of in regard to the number of leaflet based on herbarium specimens leaflets, and was only known from a pairs. This taxonomy was followed in alone, but combined with ecology, few specimens collected by Ying et al. (2011) in Flora of in phenology and geographic Buchanan-Hamilton and ‘Wallich’ which they also subsumed many of distribution we believe that it is

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Mahonia acanthifolia (top) and M. napaulensis (bottom).

The leaf of M. napaulensis has leaflets at the narrower Mark Flanagan end of its variable range.

possible to delimit separate species Horticultural literature species that can be cultivated in the within this complex. In the horticultural literature the open in the British Isles. It is hardy The situation may be comparable situation has been similarly confused in the southern and western parts of to Sino-Himalayan Taxus where and inconsistent, with only Herklots the country, but needs a sheltered some authors have recognized (1964) and Bean (1973) having come position. It received a First Class several species based on subtle to what we believe is the correct Certificate when shown from morphological differences and conclusion. Windsor Great Park on 25 geographic range, whereas others Geoffrey Herklots, the first November 1958. The plant in the have preferred to combine them British advisor at Godavari, Nepal’s Savill Gardens, growing on a wall near within a variable and wide-ranging national botanic garden, where he the propagating houses, is a cutting Taxus wallichiana. Recent molecular was succeeded by the first author, from the F.C.C. plant; it has attained studies analyzing the DNA of Taxus wrote: ‘I was puzzled by the fact that a height of 9ft in twelve years (1971).’ populations across the whole range the shrubs at lower elevations The following descriptions and show that this complex comprises of [M. napaulensis] – including those observations are presented in the several genetically distinct entities, wild in my garden at Godavari – hope that further misunderstanding some of which correspond to flowered in the early months of may be prevented. The main previously named species and others the year, whilst those growing differences between the two species which have now been described as between 7,000 and 8,000 feet are summarised in the table on p98. new species (Poudel et al. 2012). [M. acanthifolia, 2130–2440m] It would appear that Asian flowered in the autumn, especially Mahonia napaulensis Mahonia is ripe for a similar October, and bore their black fruits This is an evergreen shrub to 2 or 3m approach. However, it should be in abundance in April.’ in height, but frequently less, acknowledged that current Bean added: ‘in cultivated plants apparently localized in and around phylogenies based on DNA there is also a difference in flowering the Kathmandu Valley, especially on sequences show that Mahonia is time: late autumn and early winter the southern hills. Although nested within Berberis, and so there for M. acanthifolia, early spring for attractive in the wild it is generally of may need to be some generic level M. napaulensis. In foliage limited horticultural merit, being reassignments. M. acanthifolia is the finest of all the borderline hardy and best suited ➤

June 2014 97 taxonomy for cultivation in warmer parts of the Britain and Ireland. It is far less majestic than M. acanthifolia, having foliage with fewer and more widely spaced leaflets (occasionally up to 8 pairs, but usually 4–6 pairs). The leaves are up to 50cm long and the leaflets up to 15 x 4.5cm, with the terminal leaflet usually not noticeably larger than the rest. Past authors have considered the leaflets to be glossy on the upper surface and of a lighter texture than the matt, thicker leaflets of M. acanthifolia, but we have found these to be unreliable characters with glossiness and texture varying greatly depending on maturity of the leaves and growing conditions. Mahonia napaulensis has a late- winter flowering period, ranging from approximately February to April, and occurs in mixed open woodland or at forest margins in the warm temperate zone, which approximates to 1,220–1,800(–1,900)m. The flowers are fragrant, borne in long, terminally arranged clusters of spreading racemes of about 20cm in length, ranging in colour from mid to deep yellow, and very occasionally pale orange. The outer sepals are 3–4 x 2mm and the style about 0.4mm long. The dark blue, heavily Mahonia acanthifolia in the wild in Sikkim pruinose, rounded fruit, about 9 x Brian Mathew 6mm, ripens in May to June. Associated species include Alnus Although uncommon in (accession number 1973-14517), as nepalensis, Berberis aristata, Elaeagnus cultivation, Walters et al. (1989) only well as the Valley Gardens, Surrey, umbellata, Leucosceptrum canum, includes it as a note under M. x media and Trewithen, Cornwall. These all Ligustrum indicum, gratissima, Brickell, verified living material can originate from the same collection Maesa chisia, Osbeckia nepalensis, be found in the collections of the (Schilling 774), with the following Prinsepia utilis, Pyracantha crenulata, Royal Botanic Gardens, Kew field data: ‘Godavari, Kathmandu Pyrus pashia, Rubus ellipticus and Schima wallichii. Mahonia Napaulensis and M. acanthifolia It has the Nepalese common names Characteristic M. napaulensis M. acanthifolia of jamane mandro, bhote chotro and mandre chotro. As an indication of Plant height 2–3m to 9m Leaflet pairs 4–6(–8) (8–)9–11(–12) its cultural significance, a 5 rupee Flowering time (Jan–)Feb–April Sept–Nov(–Dec) postage stamp with an image Habitat Warm temperate forest Cool temperate forest captioned Mahonia napaulensis was Altitude range 1,200–1,800(–1,900)m (2,150–)2,300–2,900m issued by Nepal in December 2000.

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Valley, C. Nepal, ca. 1,615m. Sweet scented flowering evergreen shrub, approximately 2.5m in height, collected in 1965/6.’ The Trewithen garden specimen is of special interest, being of the seldom seen orange-flowered form, and has only recently (March 2014) been confirmed as being a seedling from the Schilling 774 collection. Trewithen received it from Cambridge University Botanic Garden in the late 1960s (Norman Villis, pers. comm.). A cultivar of M. napaulensis named ‘Maharajah’ can also be foundat Kew and the Savill Garden, Surrey, as well as possibly elsewhere. Until relatively recently the origin of this clone was open to question. It is now apparent (Clarke 1988) that it came to Britain from India as a living plant and not, as previously thought, as having been raised from seed at Caledonia Nursery in Guernsey. This species is illustrated in Lindley & Paxton (1852) and Storrs & Storrs (1998). The coloured plate in the former was drawn in March the previous year from a plant grown at the RHS Chiswick garden. The A specimen of Mahonia napaulensis RHS had been given material by grown at Trewithen, regarded as an RBG Kew and it was thought that orange-flowered form, and raised this was the first time the species from Schilling 774 seed

Sally Hayward Sally had flowered in Europe.

In 2000 Nepal issued a stamp featuring a Mahonia acanthifolia plant identified as This is an impressive, large, evergreen Mahonia napaulensis shrub or small tree, about 7–9m in height, found throughout the Himal­ ayan midhills. It occurs in open to dense mixed cool-temperate forests at altitudes ranging from 2,150– 2,900m. It is a noble and relatively hardy species of considerable garden merit. In spite of Bean’s flattering accolade quoted above it remains an uncommon sight in Western gardens. The foliage is very striking, with individual leaves to 50cm long,

commonly bearing 9–12 pairs of ➤ Mark Watson Mark June 2014 99 taxonomy frequently overlapping leaflets to 7.5 the wild (M Flanagan, pers. comm.). Expedition to Sikkim (AGSES 006). x 4cm, the terminal leaflet being Associated species include Hedera RBG Edinburgh has several plants slightly longer than the lateral pairs. nepalensis, hookerianum, Ilex collected by D Long and S The species has an autumn dipyrena, Osmanthus suavis, Piptanthus McDermott (21983) in May 1992 flowering period, immediately post- nepalensis, Prunus cornuta, Sarcococca from Helambu, central Nepal monsoon, ranging from early Sept­ hookeriana and Sorbus vestita. (accession number 19922354). ember through to early December. Fine specimens are to be found in Published illustrations of this The fragrant flowers are deep yellow, the Temperate House at RBG Kew species are included in Phillips & Rix produced in terminal, spreading, (accession number 1962-43701) and (1989, photographed at Savill densely arranged racemes to 25cm in in the collections at the Savill Garden, Windsor), Herklots (1964), length. The outer sepals are about 1.5 Garden. Both of these specimens Polunin & Stainton (1984), and x 1.5mm, and the style is 1-1.5mm can be traced to a seed collection Lancaster (1995), all under the name long. The fruit are of a similar colour made in about 1964 by Herklots at ‘M. napaulensis’. and size to M. napaulensis, but more 2,290m on Sheopuri (Shivapuri), The Nepalese distinguish between ovoid, and ripen slightly earlier in north of Kathmandu, under the these two species and give this one April to June. It is interesting to name ‘M. napaulensis’. In addition to the common names of kesari or record that both Nepalese Mahonia the Herklots gathering, the Valley keshari. Both species are used for species follow the same flowering Gardens also holds plants from the firewood, and their fruits are eaten sequence in cultivation as they do in 1983 Alpine Garden Society and reputed to be a diuretic, a demulcent and helpful in easing references dysentery. The bark of both is used Ahrendt, LWA (1961) Berberis and Evans, London as a dye and the juice of the bark is Mahonia: A taxonomic revision. Manandhar, NP (2002) Plants and said to treat inflammation of the eye J. Linn. Soc. (Bot.) 5(369): 1–410 People of Nepal. Timber Press, Oregon (Manandhar 2002). Bean, WJ (1973) Trees and Shrubs Phillips, R & Rix, M (1989) Shrubs. Hardy in the British Isles. Vol. 2. 8th Pan Books Ltd, London Conclusion edition. John Murray, London Poudel, RC, Moeller, M, Gao, LM, Boufford, DE (2013). Mahonia Ahrends, A, Baral, SR, Liu, J, In our opinion the differences () in Asia: typification, Thomas, P & Li, DZ (2012) Using between these two species are both synonymy and notes. Mem. New York morphological, molecular and Climatic clearly marked and readily analyzed, Bot. Gard. 108: 251–283 data to delimitate yews along the so much so that it is difficult to Clarke, DL (1988) WJ Bean: Trees Hindu Kush-Himalaya and adjacent understand how and why the and Shrubs Hardy in the British Isles, regions. PLoS ONE 7(10): e46873. confusion has persisted for so long. Supplement. John Murray, London doi:10.1371/journal.pone.0046873 Fedde, F (1901) Versuch einer Polunin, O & Stainton, A (1984) monographie der gattung Mahonia. Flowers of the Himalaya. Oxford Tony Schilling vmh was Engl. Bot. Jahrb. Syst. 31(1): 30–133 University Press, Oxford Curator of Wakehurst Place, Sussex, Grierson, AJC (1984) Berberidaceae. Storrs, A & Storrs, J (1998) Trees and from 1967 to 1991 and now gardens In: Grierson, AJC & Long, DG (eds) Shrubs of Nepal and the . in northwest Scotland Flora of Bhutan, Vol. 1, Part 2. Royal Book Faith India, Delhi Botanic Garden Edinburgh, Edinburgh Walters, SM, Alexander, JCM, Dr Mark Watson studies the Press, JR, Shrestha, KK & Sutton, Brady, A, Brickell, CD, Cullen, J, flora of the Himalayas at Royal DA (2000) Annotated Checklist of the Green, PS, Heywood, VH, Botanic Garden Edinburgh Flowering Plants of Nepal. Natural Matthews, VA, Robson, NKB, History Museum, London Yeo, PF & Knees, SG (eds) (1989) Herklots, GAC (1964) Flowers of The European Garden Flora, Vol. 3. the Valley of Nepal. J. Roy. Hort. Soc. Cambridge University Press, 89(7): 294–300 Cambridge acknowledgements Hooker, JD & Thomson, T (1855) Ying, JS, Boufford, DE & Brach, We would like to thank Chris Flora Indica, Vol. 1. Pamplin, London AR (2011) Mahonia. In: Flora of China Brickell, David Cooke, Mark Lancaster, R (1995) A Plantsman in Editorial Committee (eds) Flora of Flanagan, Pam Hayward, Andrew Nepal. Antique Collectors’ Club, China, Vol. 19. Science Press, Beijing, Jackson, David Jewell, David Long, Woodbridge, Suffolk and Missouri Botanical Garden Press, Gary Long, Brian Mathew, Henry Lindley, J & Paxton, J (1852) Paxton’s St Louis Noltie, Michael Taylor and Flower Garden, Vol. 3. Bradbury & Norman Villis.

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