cultivated taxonomynews Issue 6 ■ September 2018

Ceci n’est pas une plante

A floristics for the 21st century HORTAX cultivated plant group CPT News ■ Cultivated plant floristics: a highly necessary study

James Armitage holistic studies of organisms in a still have a responsibility to Editor defined environment. provide the taxonomic data required by their users. Cultivated plant floristics has The importance of this distinction existed as a special branch of is that it has created a false If it is shocking how little regard is floristic study for nearly a century, separation, in environmental paid to taxonomy in general, it is since the publication in 1924 of terms, between that have equally shocking how little regard L H Bailey’s Manual of the most arrived of their own accord and is paid by wild plant taxonomists common or significant of those that have been planted. to the highly necessary study plants grown in the continental The artificiality of this conceptual of cultivated plants. In the United States and Canada. The division comes most sharply developed world the greatest gap concept of the Horticultural into focus when considering remaining in botanical knowledge or is now well urban ecosystems. Here, the is of plants in cultivation. Given recognised and some large and farcical situation arises of the field impressive examples, often botanist who records a native running to several volumes, have species (whatever that The farcical situation been produced for various parts may mean in an entirely arises of the field botanist of the world, including , manmade environment) seeded Hawaii, south-eastern Australia, into a crack in the pavement but who records a native South Africa and Spain. These in doing so ignores thousands species seeded into a works are extraordinary efforts of tons of respiring, functional in cataloguing and classification biomass, providing habitat for crack in the pavement often achieved by only a handful who knows how many other ‘but ignores thousands of individuals operating with very living things, simply because it of tons of respiring limited resources. was planted. For the practical purposes of understanding urban functional biomass simply It might be assumed that Garden environments, the “rules” by because it was planted. are straightforward which field botanists operate are equivalents of those far more simply unhelpful. numerous Floras dealing with wild that the majority of the world’s plants, but this isn’t quite the case. Taxonomy of all sorts is taken population now live in urban Garden Floras usually contain for granted to an extraordinary zones, it is simply astonishing how keys and descriptions, taxonomic degree. Without the framework little we know of the plants that assessment and synonymy for reference and communication dominate towns and cities. but some other elements are it provides all further biological generally absent. Ecological investigation is impossible. With A change in the culture and considerations are either missing justification might taxonomists perceptions of botanists will not or replaced with cultivation feel they are unappreciated occur overnight but I hope this advice or a hardiness rating and by their fellow scientists who special edition of CPT News will there is usually no assessment seldom make the effort to be seen as a call to action. There of abundance or range. This has understand the discipline upon is so much that can be done now tended to cast Garden Floras which their own lines of enquiry to define, develop and provide as checklists with associated depend. But undervalued as infrastructure to the emerging identification guides rather than taxonomy may be, taxonomists discipline of urban floristics and

2 ■ September 2018 the study of cultivated plants in general.

As with so many things, technology has made it possible to tackle subjects which would have been insurmountable even two decades ago. The vast store of information we have amassed about cultivated plants, in journals, books, nursery catalogues, herbaria, registers and so on, hitherto extremely dispersed and to most people largely inaccessible, can now be digitised and brought before the world. With an organised and collective effort so much is possible. How about a web- based portal to access digitised nursery catalogues? or an online herbarium of urban plants? or a database to plot records of cultivated plants and display their global distribution? In the coming years image recognition software is likely to advance to such a state that an army of citizen scientists armed only with an iPhone and a sense of curiosity about their surroundings will be able to provide more data on cultivated plants than can presently be processed or understood. I suggest that an International Conference on Urban Floristsics is required to assess resources, identify priorities and set targets.

I hope the articles that follow will offer some idea of what the taxonomic study of cultivated Cover. Doronicum × plants can produce, why the What is cultivated plant excelsum ‘Harpur Crewe’. work is so necessary and, with RHS / Adam Duckworth. collaboration and effort, what floristics? Above. RHS / Julian might be achieved in the future. ■ The identification and Weigall. enumeration of the cultivated Membership of Hortax is entirely plants of a given area free of charge. If you would like to become a member please contact [email protected]

HORTAX 3 cultivated plant taxonomy group CPT News ■ Global cultivated plant floristics

Roger Spencer is Horticultural Taxonomist at the Royal Botanic Victoria and chief editor of the Horticultural Flora of South- eastern Australia (now online). With Rob Cross he is an author of the CSIRO publications Sustainable Gardens and Plant Names.

T IS EASY to forget how Britain has revealed that during Plantarum (1686, 1688, 1704) rapidly and dramatically the this period there was a rapid lists some 18,700 different kinds. world’s natural landscape introduction of about 50 new , Europe’s most has changed over the last plants, mostly Mediterranean renowned naturalist of the I200 or so years, and how fruits, herbs, spices, and eighteenth century, in his entire so much of this change vegetables that Romans career assembled the names of emanated from Enlightenment imported to improve the bland about 7,700 species of flowering Western Europe – most flavours and limited nutrient plants. In 1753, less than 40 years notably imperial Britain. content of the local foods. It is before Australian settlement, he Global landscape change a telling quirk of history, and believed that the total number has come about through globalisation, that of these 50 of plant species in the world was the human redistribution of Roman-introduced plant species unlikely to exceed 10,000. plants by means of , about 36 (over 70%) are now forestry and . naturalised in Australia – a stark Though this was essentially indication of the subsequent guesswork, some more extensive Plant redistribution is a function cultural diffusion of plants across data was soon available. Imperial of culture. Aboriginals have the planet. Britain achieved a major step occupied Australia for about towards a world flora through 65,000 years, arriving on the One consequence of Western a census of wild plants growing continent more than 10,000 science’s concern for stocktaking in its colonies and described in years before modern humans has been the desire for an Floras of North America (Hooker migrated into northern Europe. inventory of the world’s wild 1829–1840), Antarctica (Hooker We do not have a single plants. At the time of the Roman 1844–1847), New Zealand confirmed record of Aboriginal Empire, about 1,350 different (Hooker 1852–1855), Tasmania plant introduction from outside plants had been recorded in (Hooker 1855–1859), West Indies Australia. the West. By 1613 an attempt (Grisebach 1859–1864), Sri Lanka by Frenchman Jean Bauhin (Ceylon; Thwaites & Hooker Apart from a few plants, to calculate the total number 1858–1864), Cape of South Africa it seems that the first major of plants in the world put the (Harvey, Sonder & W. Thistleton- influx of exotic (foreign) plants figure at about 4,000, his son Dyer 1859–1933), Hong Kong to Britain occurred during its Gaspard increasing this number (Bentham 1861), Australia occupation by Roman garrisons of published species to 6,000 (Bentham & Mueller 1863–1878) between about 45 and 410 in 1623. English botanist John and British India (Hooker 1872– CE. Archaeological research in Ray’s three-volume Historia 1897). Today the total number of

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botanically described seed plants nineteenth century, plant is our collective environmental in the world is estimated to be taxonomy blossomed, the responsibility as we shake off the about 400,000 and the Global nursery trade gathered history of nations and empires Strategy for Plant Conservation momentum, the number of on our way to a common future through the World Flora Online known plant species in the world and a shared fate. Project has set itself the target rocketed. At the same time of compiling a widely accessible cultivated plant redistribution As horticulturists we share an began in earnest, as European enthusiasm for ornamental arable land grabs occurred in plants, for the “beautiful, curious North and South America, Africa, and new”. This fascination goes Australia and elsewhere. The back to the time of the early improved transport systems spice trade, through the Age Our world today is a of the industrial revolution of Discovery to the intrepid facilitated the spread of the horticultural plant hunters as truly interconnected European agricultural system they prospected in foreign lands. and interdependent into not only the temperate Then there was the botanophilia neo-European colonies but of eighteenth century high global society. the tropics as well with their society as people like Joseph commercial plantations of Banks and Joséphine Bonaparte ‘ tobacco, cotton, breadfruit, amassed plant trophies from working list of known plant maize, bananas and more as round the world, assembling species as a step towards a part of a mostly Atlantic market them into much-admired public complete world flora. economy. and private collections. We have all wanted a share of the world’s So, from the time of European We have yet to fully digest botanical beauty and bounty as colonial expansion in the the horticultural component plant novelties and exotic plant of this major global foods have been eagerly passed transformation, from country to country. but without doubt horticulture will Though British influence went play a major part in into rapid decline after the the determination Second World War, Britain has of both cultural maintained its pre-eminent and environmental position on horticulture’s world landscapes of the stage. One indication of all future. this history can be seen when comparing the number of Our world today is a Britain’s native species – about truly interconnected 1,500 – with its number of and interdependent different cultivated plants, which global society. One is thought to be in the region of consequence of this 400,000.

Left. Digitalis purpurea was The great and undoubted introduced by the Romans. benefits of horticulture have Of the 50 plant species brought with them some down introduced to Britain by sides, as cultivated plants have the Romans, about 36 flooded the world, swamping (over 70%) are now also island floras in particular. It is this naturalised in Australia. negative effect that we need Photo. RHS / Lee Beel. to manage. In New Zealand,

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My appeal is that we indulge our passion for ornamental plants in full knowledge and consideration of its potential impact on global ‘ and sustainability. towards half the total flora is naturalised and, as in Australia, a large proportion of naturalised plants were brought into the country for horticulture. Biosecurity programmes are now needed to monitor both new plant introductions as well as existing collections and availability. This story is repeated across the world.

Ideally, as plant scientists, we should provide the global community with the best possible information, quantified where possible, on the origins and distribution of the world’s cultivated flora. In an era of globalisation we need to have a debate about the role of horticulture in world plant geography and its influence on the current world distribution of cultivated plants – how it came to be the way it is, and how we would like it to be in the future. Part of this process is the attempt at a frank appraisal of the consequences of past action.

Good management begins with a stocktake. As publication of a wild plant World Flora gathers momentum we are now also embarking on a global phase of cultivated plant inventory – building up national and regional floristic records. To tell the world story of cultivated plants we need the underlying facts and figures that tell us exactly how wild habitats were Above. Colour engraved plate from Volume 3 of Pierre-Joseph turned into cultural landscapes. Redouté’s Les Roses. This work contains a total of 369 plates depicting rose . Belgian-born Redouté achieved success For countries and regions we need at as a painter working for the French royal court tutoring Marie- least comparative numbers of wild and Antoinette and from 1798 was appointed to paint the of cultivated plants through history; records Malmaison by Joséphine Bonaparte. His published works included of plant introduction and use and the Les Roses and Les Liliacées. © RHS Lindley Collections. historical factors that drove this process;

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Right. Drosera capensis, an invasive alien in New Zealand. Photo. RHS / Janet Cubey. the extent of past and current commercial availability; records of plant redistribution to other regions of the world.

This process can be tackled from many angles. Australia, for example, has followed the British lead in having a Garden Plant Conservation Association that consists of heritage private collections, mostly of cultivated plant genera; the historical availability of plants is indicated by databases of old nursery catalogues; records are References maintained by the Australian Cultivar Registration Authority; there is an Aussie Plant Finder Bentham, G. (1861). Flora Hooker, J.D. (1858–1864). Flora and there are other databases Hongkongensis. London: Tasmaniae. London: Lovell of cultivated plants, including Lovell Reeve. Reeve. the stock lists of botanic gardens and a combined list of plants Bentham, G. & Mueller, F. Hooker, J.D. (1872–1897). Flora held by major Australian botanic (1863–1878). Flora Australiensis. of British India. London: Lovell gardens compiled by the Council London: Lovell Reeve. Reeve. of Heads of Australian Botanic Gardens. The Horticultural Flora Harvey, H., Sonder, O. & Hooker, W. (1829–1840). Flora of South-eastern Australia will Thistleton-Dyer, W. (1859– Boreali-Americana. London: shortly be online. 1933). Flora Capensis. London: London: Treuttel & Wurtz, Lovell Reeve. Treuttel, Jun., & Richter My appeal is that we indulge our passion for ornamental Hooker, J.D. (1844–1847). Flora Grisebach, A.H.R. (1859–1864). plants in full knowledge and Antarctica. London: Lovell Flora of the British West Indian consideration of its potential Reeve. Islands. London: Lovell Reeve. impact on global ecology and sustainability. ■ Hooker, J.D. (1852–1855). Flora Thwaites, G. & Hooker, J.D. Novae-Zelandiae. London: (1858–1864). Enumeratio Lovell Reeve. plantarum Zeylaniae. London: Dalau & Co.

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The ‘In Gardens of Hawaii’ project 1988–2005

GEORGE STAPLES he Bishop Museum, For the next 11 years (1988– Honolulu, Hawaii, 1999) I led a team of research began a project in assistants and collaborators worked for many years 1983 with the goal in Hawaii and abroad in on the taxonomy of Tof updating and revising preparing a horticultural flora cultivated tropical plants. Marie C. Neal’s classic manual based on rigorous taxonomic Now he focuses his on plants of the Hawaiian research and documented by taxonomic research on Islands, In Gardens of Hawaii voucher specimens, archival (1948, 1965). In 1988 I was and photographic records. the Convolvulaceae, a hired as Project Leader to Ultimately the book grew into with considerable replace Horace Clay, the an entirely new reference work, agricultural and project’s initial author, who different in scope and coverage horticultural importance. had died. from Neal’s 1965 edition of In

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Cultivars of Cassia × nealiae (left) are widespread as flowering street trees throughout the Hawaiian Islands. Photo. Forrest and Kim Starr. Right. Naupaka (Scaevola taccada). Photo. Gail Hampshire.

Gardens. Thirty-two authors the terminology used in the updated to keep pace with contributed families or chapters plant descriptions; there is changes in plant nomenclature to the book and more than 200 a bibliography of more than and the arrival of new plant taxonomic specialists provided 1,600 references cited in the introductions, which are identifications to support text; and an etymological continuous, dynamic the writing done inhouse. A glossary for the species and processes. ■ thorough rectification of the varietal names concludes the scientific plant names used in book. the new book was fundamental to the information it contains. Because there are many thousands of plants grown Design, formatting, review, in Hawaii that could not Neal, M.C. (1948). In Gardens editing, and finally publication be included in the book, of Hawaii. Honolulu: Bernice took six years (1999–2005) a companion website was P. Bishop Museum. and the new book, entitled A created to provide a more Flora (Staples comprehensive listing of Neal, M.C. (1965). In Gardens & Herbst 2005) was published garden plants grown in of Hawaii. Honolulu: Bernice by the Bishop Museum Press the Islands. The Annotated P. Bishop Museum. in 2005. It includes more Checklist of Cultivated than 2,100 species of tropical Plants of Hawaii is available Staples, G.W. & Herbst, D.R. garden plants grown in the at this link: http://www2. (2005). A Tropical Garden Hawaiian Islands and in many bishopmuseum.org/HBS/ Flora: plants cultivated in the tropical places generally. /cultivatedplants/ Hawaiian Islands and other The book is fully illustrated tropical places. Honolulu: with more than 400 line The Checklist, circa 2005, Bishop Museum Press. drawings and a selection included more than 8,000 of colour photographs; an species of cultivated plants. illustrated glossary explains Unfortunately, it is not being

HORTAX 9 cultivated plant taxonomy group CPT News ■ Varieties of plants cultivated in Spain

Daniel Guillot Ortiz is a biologist, botanist and PhD. A member of the editorial board of the scientific magazine Bouteloua, he is the author of numerous articles, focusing on the ornamental and invasive Spanish flora and the study and cataloguing of varieties of plants cultivated / commercialised in Spain in the 19th century and the first half of the 20th.

y work on the study and classification of the ornamental and alien flora of MSpain was carried out mainly between 2001 and 2016. The results have been used in the publication in scientific journals of numerous articles (more than two hundred and eighty) together with several monographs. I have also participated in the creation, together with other botanists, of Bouteloua, a Spanish journal dedicated to the study of ornamental flora from a scientific perspective, the first volume of which was published in 2006.

The results of this line of work have increased knowledge regarding the number of species and cultivars cultivated and / or commercialised in Spain, and also of the presence of these taxa as naturalised plants. Over the

Far right. Gardens of the Alcazar de los Reyes Cristianos, Cordoba. Photo. RHS / Julie Hollobone. Right. Nepeta tuberosa. Photo. Peganum.

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course of this study numerous cultivars not mentioned in recent horticultural literature were discovered. The outputs from this work can be split into two categories, discussed below. Output 1: scientific articles Alone or in collaboration with other authors, I have published numerous scientific articles that have increased the number of cultivars known in Spain, and that generally adhere to one of four types:

a. The study of the alien flora of ornamental origin. As a result of this line of inquiry, works have been published where cultivars belonging to different genera have been cited (e.g. Aeonium, Agave, Aptenia, Centranthus, Chlorophytum, Crassula, Hedera, Ipomoea, Lantana, Opuntia).

b. Data contributed by historical Spanish botanical works. This has contributed to our knowledge of genera such as Lactuca, Malus, Pyrus, Rosa, Allium, Dahlia and Daucus as cultivated plants in Spain. I have also published articles with broader cataloguing works of cultivars marketed in this historical period, for example ‘Hacia una base de datos de variedades de plantas cultivadas en España en el siglo XIX primera mitad del XX’ (‘Towards a

Left. Ophrys apifera. Photo. RHS / Tim Sandall. Above right. Iris xiphium. Photo. Gail Hampshire.

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of catalogues of Spanish and foreign nurseries selling their products in this geographic area. Another novel aspect in Spain was the inclusion of a large number of cultivars: 2,166. Current work

My work at present incorporates several areas of activity:

♦♦ Field work in different parts of the Iberian Peninsula, cataloguing the ornamental flora. ♦♦ The creation of a database of plant varieties cultivated in the 19th century and the database of varieties of plants hybrids observed in the alien first half of the 20th century cultivated in Spain in the 19th flora (e.g. Agave gonzaloi, in Spain. century and first half of the A. × rossellonensis, A. × ♦♦ The creation of a database 20th’; Guillot, 2014) and ‘Nuevos cavanillesii, Lavandula × of varieties cultivated and datos acerca de cultivares cavanillesii, L. × glaucescens, marketed today in Spain. comercializados en España en Opuntia ‘L’Horta Nova’). el XIX y la primera mitad del XX’ (‘New data about cultivars commercialised in Spain in the Output 2: larger XIX and the first half of the XX’; Guillot, D., Mateo, G. & Guillot 2016). works Roselló, J.A. (2009). Claves Nine larger works have been Para la Flora Ornamental c. The study of the Spanish published, focusing on various de la Provincia de Valencia. ornamental flora. I have groups of non-native ornamental Monografias de Bouteloua published alone or in plants dealt with taxonomically 1. collaboration with other authors or geographically. Perhaps the numerous articles focusing on most important work is the Guillot, D. (2014). Hacia the study of the ornamental monograph entitled Claves una base de datos de flora, citing many cultivars Para la Flora Ornamental de variedades de plantas grown in Spain. Some of these la Provincia de Valencia (Keys cultivadas en España en el works focused on the study of to the Ornamental Flora of the siglo XIX primera mitad del the ornamental flora of specific Province of Valencia; Guillot et XX. Bouteloua 17: 16–41. geographical areas or in the al., 2009). The first work of its cataloguing of cultivars. kind published in Spain, it is Guillot, D. (2016). Nuevos a study of ornamental plants datos acerca de cultivares d. New species and cultivars. at the provincial level, based comercializados en España During this period I have on extensive fieldwork in en el XIX y la primera mitad described in collaboration with the core urban area of each del XX. Bouteloua 25: 85–96. other authors for the first time municipality in the province cultivars and hybrids grown in of Valencia, complemented Spanish gardens as well as new by a comprehensive study

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Beautiful & functional

eing pretty can be however, beginning to realise a double-edged this may be a false economy; sword. Sometimes adding ornamentals to “grey” people may not see infrastructure may actually make Bpast your beauty to realise urban life worth living – by you have other qualities literally bringing more life back and merits! This could be to our cities. Although scale may the dilemma ornamental be an important factor here - the plants find themselves in. more greenspace, the greater Ornamental plants are the benefits – even providing defined here simply as any ornamentals with a limited Ornamental plants have been plant used conventionally foothold in our concrete jungles, cultivated almost exclusively in a garden or wider may pay us great dividends in for their aesthetic appeal. landscape due to their return. Ross Cameron from the aesthetic appeal (and may Department of Landscape, include true species, as This debate about urban space University of Sheffield, well as selected forms or has focused the mind on what however, outlines that hybrids). exactly ornamental plants bring to our urban environments, and ornamentals can provide Ornamentals may be great can we justify their inclusion. a range of other benefits in parks and gardens for Being pretty does not hold much (ecosystem services), and that creating the “Wow” factor, weight with policy makers, but these may merit their wider but giving them space in our cultivation in the urban crowded towns and cities landscapes of the future. has not been a priority in Right. RHS Garden for a Changing recent years, especially when Climate, designed by Andy Clayden every square metre seems and Ross Cameron (Sheffield to be required for new housing, University); RHS Chatsworth roads and car parks. We are, Show 2017. Photo. RHS / Joanna Kossak.

14 ■ September 2018 being functional might. Over ♦♦ environmental services, with ♦♦ services based on health or the last few years, researchers a capacity to: socio-economic benefits, have started identifying the including: benefits parks, gardens and ▪▪ absorb rainwater, and other urban greenspaces thus reduce the risk of ▪▪ opportunities for physical provide for human society flash flooding within city exercise; (urban ecosystem services), and landscapes; ▪▪ the provision of relaxing, more specifically how different ▪▪ improve air quality; restorative environments plant taxa contribute to this ▪▪ reduce city centre with benefits for human service provision. Ornamentals air temperatures (i.e. mental health; play a key role here, largely mitigation of the urban ▪▪ improving community because they already have the heat island effect); relations through a better public “on their side” – simply ▪▪ reduce energy loss “sense of place”; because they look attractive. from nearby offices and ▪▪ reducing certain forms of This public acceptance is further houses; crime; strengthened when people ▪▪ abate the effects of noise; ▪▪ enhancing human realise the other benefits ▪▪ stabilise soil and remove / attention span and ornamental plants (and their inactivate soil pollutants improving educational associated landscapes) offer. So (phytoremediation); achievement; what are these services? They ▪▪ provide habitat for ▪▪ providing financial can be divided into: wildlife. benefits.

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Further research is required to substantiate some of these claims, but the evidence to date is encouraging. Ornamental plants strategically placed around buildings can reduce the need for artificial air conditioning in summer, and conversely reduce energy loss in winter (perhaps by as much as 20–30% in a UK setting; Cameron et al. 2015; Liu & Harris 2008). Moreover, some ornamental plants seem to perform better than others; for example, a green roof planted with may reduce surface temperatures by 12°C, compared to the performance of the “standard green roof veneer” of Sedum spp. (Blanuša et al. 2013). Ornamentals with large total surface areas (e.g. long needle pines or ornamental grasses) are most effective at capturing and storing rain water. Even with groundcover species, plants such as Dianthus ‘Haytor White’ (intricate fine ) hold 25% more water than a similarly sized glossy-leaved subject like Vinca minor.

Well-designed landscapes can help reduce Research has shown that some ornamental plants, such stress and tension in those who view them, with as Stachys byzantina (above), provide more than a single naturalistic garden styles cited as being a highly ecosystem service. Photo. RHS / Carol Sheppard. “stress restorative” form of landscape (Ivarsson & Hagerhall 2008); the presence of flowering plants being a significant component in promoting positive responses. Such aspects are not superficial or subtle – neighbourhoods in the USA with well- cared-for green plots and community gardens have been shown to have reduced levels of gun crime (Branas et al. 2011). In gross financial terms too, ornamental landscapes hold their own; for example, the garden industry in the UK is worth £5 billion pa, and one in three tourists to the UK will visit a park or garden during Well-designed landscapes can help their vacation.

reduce stress and tension in those who There is growing evidence view them, with naturalistic garden styles that the benefits of a given green space are, to some cited as being a highly ‘stress restorative’ extent, determined by the form of landscape. composition of the plants ‘ present (Cameron & Blanuša 2016). As outlined above, not all taxa are uniformly beneficial. Indeed, some species and cultivars may have significant drawbacks (e.g. may need excessively high levels of resource to ensure their survival) or even make some urban problems worse. For example, Eucalyptus species are thought to

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Fine-leaved plants such as Dianthus (below) hold 25% more water than a similarly sized glossy-leaved plant such as Vinca minor (left). Photos. RHS / Tim Sandall (left), RHS / Carol Sheppard.

exacerbate problems of poor air quality through the release of volatile chemicals from the leaves. Thus further research is warranted to determine those ornamentals that are beneficial, urban vegetation and it is at and for what particular service, this point that cultivated plant and those that are not. It is taxonomy and ecology meet. hoped that in time urban plant communities may be designed Hopefully, cultivated ornamental not only for their aesthetic plants will always have a place in appeal, but also because they our society for their fragrance and optimise the environmental immense beauty (after all, making performance of the landscape people happy is a significant or provide the greatest social service in its own right). benefits to the citizens that live Identifying their other wider around them. But to understand functions and benefits, however, urban ecosystems as they are may be key to ensuring their now it is essential to study, full appreciation and potentially quantify and catalogue the helping them move up the plants that currently constitute political “priority ladder”. ■

Cameron, R.W., Taylor, J. & Blanuša, T., Monteiro, M.M.V., Branas, C.C., Cheney, R.A, Emmett, M. (2015). A Hedera Fantozzi, F., Vysini, E., Li, MacDonald, J.M., Tam, V.W., green façade – energy Y. & Cameron, R.W. (2013). Jackson, T.D., & Ten Have, performance and saving Alternatives to Sedum on T.R. (2011). A difference-in- under different maritime- green roofs: can broad leaf differences analysis of health, temperate, winter weather perennial plants offer better safety, and greening vacant conditions. Building and ‘cooling service’? Building and urban space. American Journal Environment 92: 111–121. Environment 59: 99–106. of Epidemiology 174(11): 1296– 1306. Liu, Y., & Harris, D.J. (2008). Ivarsson, C.T. & Hagerhall, Effects of shelterbelt trees C.M. (2008). The perceived Cameron, R.W. & Blanuša, T. on reducing heating-energy restorativeness of gardens – (2016). Green infrastructure consumption of office assessing the restorativeness and ecosystem services – is buildings in Scotland. Applied of a mixed built and natural the devil in the detail? Annals Energy 85(2): 115–127. scene type. & of Botany 118(3): 377–391. Urban Greening 7: 107–118.

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Recording New Zealand’s cultivated flora

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Left. Metrosideros umbellata Background © Stan Shebs. In 1958, the Royal New Zealand Institute of Horticulture (RNZIH) was appointed the International Cultivar Registration Authority (ICRA) for New Zealand native plants.

Since then, several associated cultivar checklists / registers have been published, for Leptospermum (Metcalf, 1963), Cordyline (Heenan, 1991a), Phormium (Heenan, 1991b), Sophora (Heenan, 1992), hebes (NZ native Veronica and allied genera; Metcalf, 2001), and Metrosideros (Dawson and Heenan, 2010).

From 2011, the RNZIH have re- embarked on a New Zealand Plant Collections Register project to digitise plant names (species and cultivar names from New Zealand nursery catalogues and other specialised horticultural literature) and record online cultivated plant collections held throughout New Zealand (from private garden collections, botanic gardens, public parks Murray Dawson and reserves, and arboreta). is journal editor, Aims

webmaster and The collections register aims member of the to resolve several issues surrounding cultivated plants. national executive First and foremost, there is a of the Royal New major lack of knowledge and poor cataloguing of which Zealand Institute of cultivated plants are present Horticulture. For his in New Zealand. We don’t fully day job, he works know: as a botanist at ♦♦ What is in this country ♦♦ What it is called, or Manaaki Whenua – ♦♦ Where it is growing. Landcare Research. HORTAX 19 cultivated plant taxonomy group CPT News ■

In comparison to the extensive diversity of plants found only in cultivation, perhaps comprising 25,000–40,000 taxa, New Zealand’s much smaller flora of native (endemic and indigenous) and naturalised (weedy) species are well known and documented comprehensively. A running total (at http://www.nzflora.info) indicates that there are currently 2,482 native New Zealand species compared with about 2,819 fully naturalised species.

Dr Keith Hammett, breeder and President of the RNZIH, summed up the cultivated plants problem by saying “Managing the country without knowing everything in the flora is like managing a supermarket without knowing So far, the most notable of these driven off iNaturalist NZ (https:// everything on the shelf” resources uploaded by the RNZIH inaturalist.nz) and its USA-derived (Hammett in Dawson, 2010). is the Duncan and Davies nursery parent platform iNaturalist (www. catalogue collection. Founded inaturalist.org). Functionality New Zealand has stringent in the late 1800s, Duncan and is rich, and includes project biosecurity regulations, and Davies was New Zealand’s most creation, image upload, custom importation of species deemed prominent plant nursery. More fields, geolocation, community to be “new” is difficult and than 10,000 pages have been feedback and identification, and expensive. Lack of knowledge scanned from 184 catalogues import and export options. The and ineffective cataloguing dated from 1925 to 1994. These iNat smartphone app effectively of which cultivated plants are are accessible on the RNZIH turns portable devices into field already present in New Zealand website for non-commercial use data recorders for logging plant severely hampers biosecurity (at www.rnzih.org.nz/pages/ collections in situ. management, both pre- and nurserycatalogues.html), and post-border, as well as impairing help document when cultivars Current work effective management of living and species were first recorded collections, plant exchange, in cultivation and how rare or Current work on the New availability of breeding material, common they became. These Zealand Plant Collections and conservation of rare plants online PDFs currently lack text Register project is twofold. and heritage cultivars. layers, with Optical Character Firstly, the RNZIH need to fully Recognition (OCR) text layers yet mobilise the wealth of cultivated Progress to be added. plant names generated from the horticultural literature. Secondly, For this project, many thousands A working list of some of the of names – including botanical cultivated plant collections held Above. Cordyline australis ‘Sunrise’, names (e.g. genera, species, throughout New Zealand is bred in New Zealand in the 1990s. subspecies, varieties and aggregated on the RNZIH website It is the result of a cross between cultivars), synonyms and common (at www.rnzih.org.nz/pages/ ‘Purple Tower’ and ‘Torbay Dazzler'. names – have been digitised. plantcollections.html). This is Photo. RHS / Carol Sheppard.

20 ■ September 2018 we wish to extend the range Useful digitisation tools scientific names contained within and number of living plant PDFs and other documents. The collections recorded. During the course of this project, Chrome browser NameSpotter the RNZIH have used a range of extension usefully harvests The RNZIH are also exploring useful software and online tools. names from webpages. options to integrate their These should prove useful for cultivated plant names resources other plant name digitisation Once you have generated into a taxonomic database projects. a list of botanical names for platform. EDIT Taxonomic checking, the Taxonomic Name Editor (https://cybertaxonomy. Foxit PDF Editor (now Resolution Service (http://tnrs. eu/taxeditor/) is the only open discontinued) and Adobe iplantcollaborative.org/) corrects source solution that we know of, Acrobat Pro were used for and standardises plant names by but it has not been updated for cleaning and optimising the matching your list (up to 5,000 several years. This powers several scanned PDFs. ABBYY FineReader names at a time) simultaneously database driven taxonomic was used for OCR, and remains against several international websites, with Palmweb – Palms the industry standard. databases (including The Plant of the World Online (www. List and Tropicos) and generates palmweb.org) providing an The Global Names Recognition family names and author excellent example. and Discovery tool (http://gnrd. authorities. ■ globalnames.org/) extracts Is the EDIT Taxonomic Editor, or a platform like it, one that other ICRAs could support and adopt? References There must surely be a common need for a tool that manages all Dawson, M.I. (ed.) (2010). Heenan, P.B. (1991b). Checklist of our respective cultivar registers. Documenting New Zealand’s of Phormium cultivars. cultivated flora: “A supermarket Lincoln, New Zealand: Royal Ideally, the NZ cultivated with no stock inventory”. New Zealand Institute of names resources should also Report from a TFBIS-funded Horticulture. be federated through the New workshop held in Wellington, Zealand Organisms Register New Zealand on 9th September Heenan, P.B. (1992). Appendix 1: (www.nzor.org.nz) initiative. 2009 (Available at https:// Checklist of Sophora cultivars. NZOR is an online taxonomic www.landcareresearch.co.nz/ In: The origin of Sophora names database that aims “to publications/researchpubs/ ‘Gnome’ and the growth create an accurate, authoritative, Report-documenting_New_ habit of Sophora ‘Earlygold’. comprehensive and continuously Zealands_cultivated_flora.pdf) Horticulture in New Zealand 3(1): updated catalogue of taxonomic 2–6. names of all New Zealand biota Dawson, M.I. & Heenan, P.B. and other taxa of importance to (2010). Checklist of Metrosideros Metcalf, L.J. (1963). Checklist New Zealand.” The New Zealand cultivars. New Zealand Garden of Leptospermum cultivars. horticultural community are Journal 13(2): 24–27. (www. Royal New Zealand Institute of currently exploring the best rnzih.org.nz/RNZIH_Journal/ Horticulture (RNZIH) Journal 5: ways to make these plant names Pages_24-27_from_2010_ 224–230. available. Vol13_No2.pdf) Metcalf, L.J. (2001). International To expand the working list of Heenan, P.B. (1991a). A cultivar register of hebe cultivars. cultivated plant collections, we checklist for the New Lincoln, New Zealand: Royal are prioritising the New Zealand Zealand species of Cordyline New Zealand Institute of Gardens Trust listings (https:// (Asphodelaceae). Horticulture in Horticulture. www.gardens.org.nz), which New Zealand 2(1): 8–12 feature gardens to visit.

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survives, until we come to the last Cataloguing cultivated plants in quarter of the 19th century, when both the Cape and Natal colonies produced useful material. In Natal, John Medley Wood was appointed Curator of the Durban Botanic Garden in 1882, and produced a long series of annual SOUTHERN reports, as well as three guides, listing the plants in the Garden (Wood 1883, 1889, 1897) and a checklist (Wood 1915). Wood also founded the Natal (now KwaZulu- Natal) Herbarium, which then as AFRICA now includes a small collection of cultivated plants.

In the previous year, the Cape Where are we, and what still Colony established a Department of Forestry under Count Médéric de Vasselot de Régné and Joseph needs to be done? Storr Lister. The latter established an at Tokai on the Cape Peninsula (Immelman et mong the earliest at Kirstenbosch; the garden is al. 1973); his specimens from surviving but a memory, and the site has here are among the earliest in specimens of for many years been occupied the former Forestry Herbarium Aspecifically by a school. The actual plants (PRF, now incorporated in the cultivated plants in southern the good Baron grew may be National Herbarium, Pretoria Africa is a small collection seen as a bit of a disaster: he (PRE)). After Union, the Forestry made by Dr Ludwig Pappe evidently introduced no less in the Cape Town garden than eight of the ten worst of Baron Carl F.H. von weeds in the Cape through his Ludwig in the 1830s (Glen garden. & Germishuizen 2010). The specimens are still to be found Hardly anything that contributed in the Compton Herbarium to horticultural taxonomy

grew up in a family of keen and nature HUGH GLEN enthusiasts in Johannesburg. He completed his PhD at University of Cape Town, with a thesis on a group of Mesembryanthemaceae, after which he joined the Botanical Research Institute (now SANBI) in Pretoria. A spell as South African Botanical Liaison Officer at Kew did his appreciation of the variety of cultivated plants the world of good. After returning to Pretoria he worked on Aloe for the Flora of Southern Africa, and then took over the National Herbarium’s collection of cultivated plant specimens. He has served on two committees of the International Code of (now International Code of Nomenclature for Plants…) and the IUCN Commission for the Nomenclature of Cultivated Plants. He retired in 2013 and lives in Durban, where he divides his time between “recreational botany” and railway history. He still enjoys working on cultivated plant taxonomy, especially enjoying plants that are “bigger than me”.

22 ■ September 2018

Department established arboreta university herbaria also acquired and others quite common in in many parts of the country material of cultivated plants, cultivation but absent from the where numerous tree species usually brought in by members list) in this publication. were grown experimentally. of the public for identification. Specimens of there were duly When the present author sent to the Forestry Herbarium, Although efforts were made to assumed responsibility for the which became a major document the indigenous flora collection of cultivated material in repository for knowledge of throughout the 20th century, PRE, soon joined by the material cultivated trees. At the same precious little was done about in PRF, it was self-evident to him time, the National Herbarium garden, crop and forestry plants. that a listing of the specimens and its offshoots in Durban, Ken Cunliff produced a long in the collection was a vital Grahamstown, Stellenbosch and series of studies of individual management tool. Accordingly, Windhoek (before Namibian species in the Tree Society’s a simple database was designed independence) acquired – journal Trees in South Africa, and to be compatible with the main usually without any specific there are garden manuals by herbarium database and set up. effort – collections of smaller Pienaar (1987) and others. The This has now been incorporated cultivated plants. Similarly, only checklist of this period was in the main SANBI specimen Von Breitenbach’s (1984) tree list. database. The first product of Left. Bronze bust of John Medley This is still widely used, but the this was in the form of a progress Wood (1827–1915). Above. A pathway present author has a problem report (Glen, 1999). This was in the Durban Botanic Garden, the with the number of “ghosts” followed by a checklist of taxa oldest surviving (trees listed with no evidence of represented by material seen in Africa. Photos. Hugh Glen. their having been grown here, for the database, to which was

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24 ■ September 2018

References Glen, H.F. (1999). The State of Horticultural Taxonomy in South Africa, in S. Andrews, A.C. Leslie & C. Alexander (eds.) Taxonomy of Cultivated Plants: Third International Symposium: 469–470. Royal Botanic Gardens, Kew. Glen, H.F. (2003). Cultivated Plants of southern Africa. Johannesburg: Jacana. Glen, H.F. (2008). What is this Tree? Towards an electronic Key to Trees cultivated in southern Africa. Proceedings of the 5th International Symposium on the Taxonomy of Cultivated Plants 121–125. Glen, H.F. & Germishuizen, G., eds. (2010). Botanical added, for each family and , checklist being prepared of the Exploration of southern Africa, a list of references to literature in trees in Durban Botanic Garden, edn 2. Pretoria: SANBI. the PRE collection (Glen 2003). and a key being prepared to “all” Glen, H.F. & Van Wyk, A second progress report, on trees in southern Africa, both A.E. (2016). Guide to Trees a proposed electronic key to indigenous and introduced, by introduced into southern Africa. cultivated trees, followed (Glen a team including both Prof. Van Cape Town: Struik Nature. 2008). The most recent product is Wyk and the present author. Immelman, W.F.E., Wicht, C.L. a “field” guide to introduced trees & Ackerman, D.P. (1973). Our (Glen & Van Wyk 2016). After many years of hearing all Green Heritage: The South exotic plants decried as “invasive African book of Trees. Cape Ideally, these products would aliens” (in fact, only just over Town: Tafelberg. be supplemented with 2% of all exotics are declared Pienaar, K. (1987). The A–Z of comprehensive datagathering invaders), it is good to note Garden Flowers in South Africa. to determine what plants are anecdotal evidence that at least Cape Town: Struik. grown where and why, and the some exotics are recognised as Von Breitenbach, F. (1984). publications would then form essential sources of firewood and National List of introduced the basis of a southern African bee fodder. Maybe one day it Trees. Pretoria: Dendrological garden flora. However, with no will be possible to convince the Foundation. staff in the country tasked with powers that be that, apart from Wood, J.M. (1883, 1889, 1897). anything resembling this, the watermelons and some niche A Guide to the Durban Botanic chance of this happening in the fruits, all our vegetable food and Gardens. Durban: Ellinger. foreseeable future. Apparently, clothing is of exotic origin, and the best approximations to therefore cultivated plants are Wood, J.M. (1915). List of Trees, this on the horizon are a new worthy of study. ■ and a Selection of Herbaceous Plants growing in the Durban Municipal Botanic Gardens. Durban: Above. Fruits of Bixa orellana (annatto) in the author’s garden in the Bennett & Davis. suburbs of Durban. The seeds may be used in cookery. Left. Dracaena draco (dragon tree) in Grahamstown Botanic Garden. Photos. Hugh Glen.

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