United States Department of lture Agricu ricultural Research Service United States Contribution Number 7 National Arboretum ' ‘ 4 ‘ e ' i ay il Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices. espa Errata for A Catalog of Cultivated Woody Plants of the Southeastern United States Page 27, in Arecastrum: = Syagrus romanzoffianum should read = Syagrus romanzoffiana. Page 32, in Buddleja: farreri Balf.f. & W.W.Sm. should read farreri Balf.f. & W.W.Sm. = crispa Benth. var. farreri (Balf.f. & W.W.Sm.) Hand.-Mazz. Page 54, in Comus: ‘Gold Star’ [C. kousa Hance] should read ‘Gold Star’ (Buerger ex Miq.) Hance. Page 69, under Euodia daniellii (Benn.) Hemsl.: include the note E. daniellii still appears widely in horticultural works, but T.G. Hartley’s revision of the genus Tetradium moves it to Tetradium daniellii (Benn.) Hartley. Page 128, in Magnolia: include the entry foetida Sarg. = M. grandiflora (L.) after ‘Elizabeth’ [M. acuminata < M. denudata]. Page 134, in Malus ‘Aldenhamensis’: ‘Niedzwetzkeyana’ should read ‘Niedzwetzkyana’. Page 135, in Malus: include the entry niedzwetzkyana Dieck = M. domestica ‘Niedzwetzkyana’ after ‘Naragansett’ [M. / hybrid #28/ x M. ‘Wintergold’. Page 136, under Malus X purpurea: ‘Niedzwetzkeyana’ should read ‘Niedzwetzkyana’. Page 156, in Prunus: ‘Albo-plena’ [P. glandulosa Thunb.] should read ‘Albo-plena’ [P. glandulosa Thunb. ex J.A. Murr.]. Page 160, in Prunus ‘Yae murasaki zakura’: (Yato zakura group) should read (Sato zakura group). Page 160, in Pseudotsuga: include the entry taxifolia (Lamb.) Britton = P. menziesii (Mirb.) Franco after ‘Oudemansii’ [P. menziesii (Mirb.) Franco var. glauca (Beissn.) Franco]. Page 180, in Rosa: banksiae Ait. should read banksiae Ait.f. Page 188, under Salix xlaestadiana Hartm.: S. cineria should read S. cinerea. Page 188, under Salix x pontederana Willd.: S. cineria should read S. cinerea. Page 196, in Syagrus: romanzoffianum should read romanzoffiana. Page 199, in Syringa: ‘Charles Giant’ should read ‘Clarke’s Giant’. Page 199, under Syringa Xchinensis Willd.: [S. X persica X S. vulgaris] should read [S. persica X S. vulgaris]. Page 203, in Thuja: ‘Cuprea’ [T. plicata D.Don] should read ‘Cuprea’ [T. plicata J.Donn ex D.Don]. Page 203, in Thuja: plicata J.Donn ex G.Don should read plicata J.Donn ex D.Don. Page 203, in Thuja: ‘Rogersii’ [T. plicata D.Don] should read ‘Rogersii’ [T. plicata J.Donn ex D.Don]. Page 203, in Thuja: ‘Zebrina’ {T. plicata D.Don] should read ‘Zebrina’ [T. plicata J.Donn ex D.Don]. Page 212, in Viburnum Mt. Fuji’: [V. plicatum Fort. f. tomentosum (Thunb. ex J.A.Murr.) Rehd.] should read [V. plicatum Thunb. f. tomentosum (Thunb. ex J.A.Murr.) Rehd.]. Page 213, in Viburnum ‘Shoshoni’: [V. plicatum Fort. f. tomentosum (Thunb. ex J.A.Murr.) Rehd.] should read [V. plicatum Thunb. f. tomentosum (Thunb. ex J.A.Murrt.) Rehd.]. Page 255, under Buddleja: farreri Balf.f. & W.W.Sm. should read farreri Balf.f. & W.W.Sm. = crispa Benth. var. farreri (Balf.f. & W.W. Sm.) Hand.-Mazz. Page 273, under Hibiscus: syriacus ‘Tamausagi’ should read syriacus ‘Tama usagi’. Page 275, under Ilex: aquifolium ‘Scotia’ should read aquifolium ‘Scotica’. Page 301, in Rosa: include the entry Xodorata (Andr.) Sweet ‘Old Blush’ after odorata (Andre.) Sweet ‘Fun Jwan Lo’. Page 301, in Rosa: include a X before the three odorata entries. Page 302, in Rosa: include the entry ‘The Fairy’ after ‘Sombreuil’. Page 305, in xSorbopyrus: ‘Bulbiformis’ should be indented under auricularis. Page 306, under Syagrus: romanzoffianum should read romanzoffiana. Page 307, under Syringa: ‘Charles Giant’ should read ‘Clarke’s Giant’. Page 321, under Palm, Queen: Syargus romanzoffianum should read Syargus romanzoffiana. PRUNUS mume Sieb. & Zucc. ‘Peggy Clarke’ [illustrator Lillian Nicholson Meyer] V ' he A Catalog of Cultivated Agriculture ngrcutra Woody Plants of the iwisas QOUtheastern United a States By Frederick G. Meyer, Peter M. Mazzeo, and Donald H. Voss Abstract Meyer, Frederick G., Peter M. Mazzeo, and Donald H. Voss. 1993. A Catalog of Cultivated Woody Plants of the Southeastern United States. U.S. Department of Agriculture, Agricultural Research Service, U.S. National Arboretum Contribution No. 7, 338 pp. This work catalogs cultivated landscape trees, shrubs, and woody climbers in a 13-state area of the southeastern United States, together with the District of Columbia. Included are approximately 5,000 entries—covering species, subspecies, varieties, forms, and cultivars—based on more than 14,000 documented voucher specimens. The burgeoning nursery business, along with the continued introduction of new cultivated plants, has added to the need for accurate application of botanical nomenclature. Many plants are misidentified in the nursery trade and among researchers, students, and home gardeners. The catalog serves as a reference guide for these groups, as well as for horticulturists, botanists, extension agents, educators, germplasm conser- vators, and those who work in botanic gardens and arboreta. Keywords: climbing plants, cultivars, gardens, horticulture, landscaping, names (botanical), nurseries, plant geography, plant names, plant nomenclature, plant taxonomy, shrubs, trees, woody vines. While supplies last, single copies of this publica- tion may be obtained at no cost from the Curator of the Herbarium, U.S. National Arboretum, 3501 New York Avenue, N.E., Washington, DC 20002-— 1958. Copies of the publication may be purchased from the National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161. February 1994 iv The United States Department of Agriculture (USDA) prohibits discrimination in its programs on the basis of race, color, national or igin, sex, religion, age, disability, political beliefs, and marital or fa- milial status. (Not all prohibited bases apply to all prog rams.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audio tape, etc.) should contact the USDA Office of Communica- tions at (202) 720-5881 (voice) or (202) 720-7808 (TDD). To file a complaint, write the Secretary of Agricul- ture, U.S. Department of Agriculture, Washing- ton, DC, 20250, or call (202) 720-7327 (voice) or (202) 720-1127 (TDD). USDA is an equal employ- ment opportunity employer. Cover: IDESIA polycarpa Maxim. [illustrator Susan M. Johnston] Contents PORC WON ensue goss citiiasensncetebacantbentetacxsieanetanes vii PCMOWICU SUNENILS 555555 sacs catensscacnscensnsacuaduetevedas vii INCPOGUCHION sc.:ccsccasies epsnan id enbastensideadeseamadiseuweaceda 1 Sy MOS and ADDICVIAUMIONS ....2ssssescerssnssasienzn cas 11 Catalog of plants and their collection sites ...... 12 Appendix A: Authors CHE” seiisisecsssvessevscesssas 218 Appendix B: Plant collection sites, cited by ACTONMYMN | gadiiicsweloseeeryioneveetevieoaws 237 Appendix C: Glenn Dale azalea cultivars documented in the U.S. National Arboretum Herbarium. .............. 248 Appendix D: Plants listed by botanical names ANG CUultiVar NAMES. sx.icscecencessaes 249 Appendix E: Vernacular naMeS ........06.s600.0 313 GENET axintaiotichiengivasseettens 313 Species and cultivars ......... 314 DCICClEd DIDMOSEADIY sasiertestecinesdienedomanecsaiiues 326 Illustrations IDESIA POlyCarpd .......cseceeeeceeeecneceneeeneeenees cover PRUNUS mume ‘Peggy Clarke’ ........ frontispiece ACTINIDIA GF GUtiG ccccesecssinvseshicseesicensenecseeccenes 22 PLIST BIA (GURU sissies oiicisija sosctientueedsnessasoescaceasins 24 BIGNONIA capreolat .........ccceceeseeceeeeeceeeeeeees 31 BRUNFELSIA australis ........ccecceceseeeeeeeseeeeees 33 CALYCANTHUS floridus ......ccceeeeeeeeeeeeeeeeeeeee 38 CHIMONANTHUS prdecox ........cseceeeeeneeeeeeees 50 DAVIDIA involucrata var. vilmoriniana ......... 63 DISANTHUS cercidifOlius ......... cece ccceeeeeeeeeee eee 66 FOTHERGILLA MAjOP oo... cseeeeeeeeceeneeeeeeeeeeeeeees 74 HALESIA COrOUNG oo. .ee cece eeeecteecneecneceneeenneeenes 77 HAMAMELIS mollis ......cceeeccseeeeceeeeeeeeeeeeeeeeees 79 FIOVEENTA, GUlCi$ scssssiiecssencdetuad vattiventousstpenceanves 88 HYDRANGEA anomala ssp. petiolaris ......... 89 ILLICIUM florid num... ecccecceseceneeceteeeeeeneees 110 ILLICIUM parviflOrum ........cceeeeeseeeeeneeeeeneees 111 JASMINUM nuiflorum vice eeeeeceeeseeeeeeeeene eee 113 CUGLANS TOGUA tics ieisssivtsws caeindt veccussdvioweenezuees 114 KOELREUTERIA bipinnata ..........ccceeeeeee eee 120 LAURUS NODUS wissusiscaccgacvnesioesencvanerenossctoaues 123 MAGNOLIA ashei (fruit)... ceeeeeeeeeeee ee 129 MAGNOLIA macrophylla (fruit) ...............00 129 MAGNOLIA tripetala w..ceeceeecceeceeecceeeeneeenees 133 MICHELIA iGO ......ccceeeecsseeeecneeeeeeeeeeeneseeenees 138 PARROTIOPSIS jacqueMontiana ..........60000 143 PSEUDOLARIX AMADIS wo. cece ee eeeectee eens 161 SCHIZOPHRAGMA hydrangeoides ............. 191 WLYRAX JQPOMCUS . accstesessnsensiivecsonadeabarteiaes’ 197 SYCOPSIS SiNeNStS: sicssecestsessseatazesavencoazestass 198 DOONA:SINCNSIS: scssezesssessvesceectetansitotecsonter ia’ 206 ULMUS parvifOlid oo. ceeceeceecccceeccneeeeeeeceeeeneeees 209 Foreword The herbarium of the U. S. National Arboretum is one of the few major herbaria to emphasize cultivated plants together with their wild progeni- tors. Its specimens support scientific research on these plants not only within the Department of Agriculture but also worldwide through a loan program. The ongoing work of the herbarium staff in addressing problems in plant taxonomy and nomenclature assists researchers, germplasm conservators, and others in plant identification and contributes to the efforts of nurseries to identify correctly the plant material they propagate and sell. A Catalog of Cultivated Woody Plants of the Southeastern United States represents the culmi- nation of more than 20 years of field work begun in 1967 that covers 13 southeastern states and the District of Columbia. The catalog has been prepared as a reference guide for nurseries, landscape architects, horticulturists, botanical and horticultural libraries, botanists, extension agents, educators, germplasm conservators, botanical gardens and arboreta, propagators, students, various units of the U.S. Department of Agriculture, plant societies, and the gardening public. It will be useful not only in the south- eastern states, but also in other parts of the United States where many of the plants listed can be found in cultivation. The catalog is based on more than 14,000 docu- mented voucher specimens critically reviewed for correctness of identification and nomenclature. With about 5,000 entries, both botanical names and cultivar names, the catalog is a comprehen- sive enumeration of woody plants cultivated in the southeastern United States. The catalog is unique, being based wholly on documented material deposited in the U. S. National Arboretum herbarium and including a guide to sites where collections were made of plants growing in cultivation. It is hoped that the catalog will, by example, encourage similar documentation of the woody landscape plants in other areas of the country and the deposit in appropriate herbaria of voucher specimens -collected for permanent reference. Allan K. Stoner Acting Director, U. S. National Arboretum Acknowledgments Many individuals, too numerous to mention, generously facilitated our collection efforts at botanical gardens and arboreta, experiment stations, college campuses, nurseries, and private gardens. We specifically acknowledge the invaluable assistance of the following specialists for their help in identifying plant specimens: W.A. Ander- son (Malpighiaceae), George Argus (Salix), Helen L. Blake (old roses), Barbara Briggs (Callistemon), C.E. Codd (Carissa macrocarpa), David W. Hall (miscellaneous Florida plants), James W. Hardin, Jr. (Aesculus), Elizabeth McClintock (Hydrangea and Myrtaceae), A. Edward Murray, Jr. (Acer), Eliane Norman (Buddleja), J.B. Phipps (Crataegus), the late Sigmund Solymosy (miscel- laneous Louisiana plants), and Charles A. Walker (old roses). T. R. Dudley contributed many voucher specimens cited in the catalog and compiled the lists of Ilex and Caprifoliaceae. We express appreciation to the Friends of the National Arboretum (FONA) and to the Southern Nurserymen’s Association for financial support that greatly enhanced our ability to collect speci- mens in the southeastern United States. We also thank Carol A. Rahbar and Franziska Walczak as volunteer collaborators for their substantive assistance in coordinating data related to the computer data base, the list of site acronyms, and attending to many other details that contributed enormously to the accuracy of the catalog. The authors are grateful for the privilege of using artwork by the late Lillian Nicholson Meyer, Susan M. Johnston, and Peggy K. Duke. A Catalog of Cultivated Woody Plants of the Southeastern United States by Frederick G. Meyer, Peter M. Mazzeo, and Donald H. Voss Scope This catalog presents a comprehensive reference list, based on documented material, of the trees, shrubs, suffruticose plants, and woody climbers cultivated in the southeastern United States. A list of acronyms identifies the collection sites for each entry. While the southeastern United States is well served by botanical manuals and other floristic works that identify native plants, such works on the cultivated woody plants (indigenous and introduced) of the southeastern states have been much neglected. The catalog contains about 5,000 entries— species, subspecies, varieties, forms, and culti- vars—in 112 plant families and 493 genera. These are based on more than 14,000 voucher herbarium specimens, most collected specifically for this project. The primary focus of the project has been a critical review for correct identifica- tion and nomenclature of material in the list. This material, now permanently deposited in the herbarium of the U. S. National Arboretum, was collected at nearly 700 sites in Alabama, Arkan- sas, Delaware, the District of Columbia, northern Florida, Georgia, Louisiana, Maryland, Missis- sippi, North Carolina, South Carolina, Tennes- see, southeastern Texas, and Virginia. This area covers about one-sixth of the continental United States and spans Plant Hardiness Zones 6b through 9a (U.S. Department of Agriculture 1990). The collection sites include botanical gardens and arboreta, cemeteries, college cam- puses, experiment stations, nurseries, private gardens, and roadway plantings. While comprehensiveness was an objective, the catalog makes no claim to completeness, since new plants are constantly being introduced to horticulture; and from a practical standpoint we were unable to visit every possible site. In genera such as Camellia, Rosa, Rhododendron, Hedera, and some others with a vast number of cultivars, completeness was simply not possible. However, Meyer is a supervisory botanist (retired) and Mazzeo is a botanist, U.S. National Arboretum, Agricultural Research Service, U.S. Department of Agriculture, Washington, DC 20002; Voss, of Vienna, Virginia, prepared the computer data base and programming for the catalog and assisted in the checking of nomenclature. a large number of plants not previously listed or reported as cultivated in the United States are included as a result of recent introductions. The catalog includes many unusual or rare plants from the living collections of the U. S. National Arboretum not well represented else- where in this country. Between 1961 and 1990, 125 cultivars in 18 genera were released by the National Arboretum to the horticultural indus- try—cultivars of Buxus, Camellia, Clematis, * Cupressocyparis, Eurya, Hibiscus, Ilex, Kalmia, Lagerstroemia, Magnolia, Malus, Metasequoia, Platanus, Pyracantha, Pyrus, Rhododendron, Ulmus, and Viburnum. The catalog also lists for the first time most of the dwarf and slow-growing conifers in the Gotelli Collection at the U.S. National Arboretum. The list of Ilex, the largest of any genus in the catalog, is based primarily on the extensive collections of living plants and voucher herbarium specimens at the U.S. Na- tional Arboretum. The authors are solely responsible for the names and identifications of the plants listed in the catalog, but in difficult genera such as Acer, Aesculus, Callistemon, Crataegus, Hydrangea, Ilex, Salix, and Viburnum, we had the expertise of specialists who generously provided names and verified identifications. In this introduction, most of the botanical names are cited without authorities, since these are properly listed with the names in the catalog; but sometimes authori- ties are cited to substantiate a point. The catalog is arranged alphabetically by the internationally accepted botanical and cultivar names, including some synonyms. Vernacular, or common, names are also included for many entries. When a species is subdivided, the epithet for the infraspecific taxon that includes the type of the species name is an exact repeti- tion of the specific epithet (an autonym) and is cited without the author's name. The list of collection-site acronyms in Appendix B identifies the sources of the documented voucher speci- mens, thereby providing information on the abundance, distribution, and hardiness range of the plants listed. Although we have not indicated the geographic origins of the plants, the cultivated woody flora of the southeastern states represents a wide diver- sity of germplasm from many countries, in particular the southeastern United States, Europe, and eastern Asia. In lesser numbers, the catalog lists plants from temperate areas of South America (southern Brazil, Uruguay, Para- guay, northern Argentina, and northern Chile), including Araucaria araucana, Brunfelsia austra- lis, Butia capitata, Calliandra tweediei, Erythrina crista-galli, Sesbania punicea, Tipuana tipu, and others. The diversity of woody landscape plants now in cultivation from South America and Central America suggests that renewed germplasm exploration in these areas would no doubt turn up other plants worth introducing for landscape use in the southeastern United States. Other areas represented in the catalog include Mexico, with Antigonon leptopus, Dioon edule, Parkinsonia aculeata, and some others; South Africa, with Carissa macrocarpa, Ochna atropurpurea, Phygelius capensis, and Tecomaria capensis; and Australia, with Casuarina cunninghamiana, Callistemon (six species), Callitris columellaris, Eucalyptus (six species), and Westringia rosmariniformis. Need for the Catalog In recent years, the nursery industry has become increasingly active in offering new plant introduc- tions, as a result of renewed interest in plant exploration and germplasm diversity. Each year introductions appear in ever-increasing numbers from all parts of the world. People are now planting a greater diversity of woody landscape plants than ever before in U.S. history. The U.S. National Arboretum has contributed significantly to this flow of new introductions from its plant breeding program and from expeditions to Japan, the People’s Republic of China, and the Republic of Korea. Some woody plants totally unknown in cultivation only a few years ago are now best- sellers in garden centers; these include Pyracan- tha ‘Mohave’ and Hibiscus syriacus ‘Diana’, both of which resulted from the U.S. National Arbore- tum plant breeding program. The influx of new plants has compounded the problems of plant identification and nomencla- ture in the nursery trade, as well as among researchers, students, and home gardeners. Many plants found in the nursery trade are misidentified. The same plant may appear under various names in different nursery catalogs, a problem that leads to nomenclatural confusion. We have observed, for example, that dwarf and slow-growing conifers are frequently misnamed in the nursery trade and by the specialists who grow them. Because of this confusion, the need is pressing to investigate the taxonomy and nomenclature not only of landscape plants but also of food, medicinal, and agronomic plants as a much-neglected aspect of horticultural botany. Access to voucher herbarium specimens makes identification of these plants much easier and far more accurate. Unfortunately, too few technically qualified botanists or horticulturists are available and willing to tackle the identification and nomencla- ture of landscape plants, leaving many plant groups in a state of perpetual taxonomic and nomenclatural confusion. Although botanical gardens and arboreta often maintain small herbaria to document the plants in their ccllec- tions, very few of the world's major herbaria are willing to incorporate specimens of cultivated plants for scientific study. The value of voucher herbarium specimens has not been sufficiently appreciated by horticulturists. Many problems related to the taxonomy and nomenclature of the plants in this catalog simply could not have been effectively investigated and resolved without the benefit of herbarium specimens. Plant Origins The area covered by the catalog encompasses much the same range as J.K. Small’s Manual of the Southeastern Flora (1933). This vast region supports the richest ligneous flora in temperate North America and may be compared only with the highly diverse woody flora of the People’s Republic of China. More than 250 species of indigenous trees occur in the southeastern United States, many of them grown as landscape plants. One of the best known and admired is Magnolia grandiflora, which ranks among the most valuable indigenous landscape trees of the United States. Now widely cultivated abroad, this magnificent flowering tree is one of America’s great gifts to the gardens of the world. Because of climatic similarities between eastern Asia and the eastern United States, countries such as Japan, Korea, and the People’s Republic of China, with Taiwan, are heavy contributors of woody landscape plants now widely cultivated in the southeastern United States. Some well- known plants of east Asian origin include Camellia japonica, Cryptomeria japonica, Ilex crenata, Juniperus chinensis, Lagerstroemia indica, Ligustrum japonicum, L. lucidum, Magnolia denudata, Rhododendron (many species), Ternstroemia gymnanthera, Wisteria floribunda, and W. sinensis.. From a horticultural perspective, the southeast- ern United States is one of the most interesting areas in the country. The oldest landscaped gardens in the United States, dating from the late 17th and early 18th centuries, are found in Virginia, the Carolinas, and Georgia. Since plants follow people, we know that many of the earlier introductions were brought by European immigrants to their new homes in America. Early plantation life in the southern colonies promoted an interest in the cash crops of to- bacco, rice, and indigo. By the end of the 17th century, ornamental plants such as boxwood (Buxus sempervirens) and garden flowers intro- duced from Europe were cultivated. The gardens at Middleton Place near Charleston, SC, date from about 1730 as one of the oldest landscaped gardens in America. About the same period, the earliest nurseries were established in Charleston. The first plant-introduction garden in America, called the “Founder's Garden,” was established at Savannah soon after the founding of the Georgia colony in 1733 by James Oglethorpe. It is recorded that about 20 to 25 exotic trees and shrubs were already in cultivation in gardens at Williamsburg, VA, by the middle of the 18th century, including cornelian cherry (Cornus mas), fig (Ficus carica), littleleaf linden (Tilia cordata), weeping willow (Salix babylonica), and the com- mon lilac (Syringa vulgaris). At the same time, about 80 species of native American trees and shrubs were cultivated at Williamsburg, includ- ing flowering dogwood (Cornus florida), American beech (Fagus grandifolia), common catalpa (Catalpa bignonioides), red buckeye (Aesculus pavia), Carolina cherry laurel (Prunus caroliniana), southern live oak (Quercus virginiana), and American holly (Ilex opaca). The introduction of the parasol tree (Firmiana simplex) about 1780 at Charleston, SC, is attrib- uted to André Michaux, a French plant explorer who lived near Charleston. American ships returning from China often landed at Charleston, and Michaux may have obtained seeds of the parasol tree from one of these ships. From the evidence at hand, it is doubtful that the common camellia (C. japonica) came directly to America on board a ship returning from the Orient. Michaux probably did not introduce the camellia to Middleton Place in 1785 as long assumed. We have identified one of the four original plants attributed to him on this site as C. japonica ‘Anemoniflora’, a cultivar that only reached England in the first decade of the 19th century and was illustrated in Curtis’s Botanical Maga- zine, t. 1654, 1814. It is more likely that the camellias at Middleton Place reached America from Great Britain after 1814 and not earlier. Categories of Ligneous Plants in the Catalog Trees The distinction between trees and shrubs is often controversial from various points of view. No two definitions totally agree. We know that some shrubs become treelike under certain growing conditions. A tree, by standard dictionary defini- tion, is a perennial woody plant usually having a single self-supporting trunk and ranging in height from 10 to more than 300 feet. Many trees fit this definition, but others do not. Indig- enous species such as Cornus florida and Vibur- num prunifolium rarely attain the stature of a tree in their native woodland habitats, but in an open sunny location these same species often become treelike. In another example, the red buckeye (Aesculus pavia) may grow to 30 feet as a single- trunked tree in the open but not more than a shrub 5 to 6 feet high in a woodland setting. Examples of indigenous trees of the southeastern United States, with their maximum height, include: Acer saccharinum, silver maple, 70 ft Aesculus flava, yellow buckeye, 70 ft Fagus grandifolia, American beech, 70 ft Fraxinus americana, American ash, 80 ft Ilex opaca, American holly, 100 ft Liriodendron tulipifera, yellow poplar, tulip tree, 100 ft Magnolia grandiflora, southern magnolia, 90 ft Magnolia macrophylla, bigleaf magnolia, 50 ft Platanus occidentalis, American sycamore, 80 ft Quercus alba, white oak, 70 ft Quercus phellos, willow oak, 70 ft Quercus velutina, black oak, 70 ft Quercus virginiana, southern live oak, 70 ft. Examples of trees introduced into the region, with their maximum height, include: Ailanthus altissima, tree-of-heaven, 70 ft, People’s Republic of China Broussonetia papyrifera, paper mulberry, 40 ft, eastern Asia to Polynesia Cedrus deodara, deodar cedar, 100 ft, Nepal and adjacent People’s Republic of China Cunninghamia lanceolata, China fir, 70 ft, People’s Republic of China, with Taiwan Firmiana simplex, parasol tree, 60 ft, People’s Republic of China Morus alba, white mulberry, 40 ft, People’s Republic of China Paulownia tomentosa, princess tree, 50 ft, People’s Republic of China Platanus < acerifolia, London plane, 60 ft, garden origin Salix babylonica, weeping willow, 60 ft, People’s Republic of China(‘?) Sapium sebiferum, Chinese tallow tree, 80 ft, People’s Republic of China Sequoia sempervirens, coast redwood, 100 ft, California. Examples of smaller trees, both native and introduced, include: Albizia julibrissin, mimosa tree, 30 ft, Iran to People's Republic of China, Japan, and Korea Amelanchier arborea, serviceberry, 35 ft, eastern United States Asimina triloba, pawpaw, 35 ft, eastern United States Buxus sempervirens, common boxwood, 25 ft, Europe Cercis canadensis, North American redbud, 25 ft, eastern United States Chionanthus retusus var. serrulatus, 25 ft, People's Republic of China, with Taiwan Cornus florida, flowering dogwood, 30 ft, eastern United States Cotinus obovatus, American smoke tree, 40 ft, eastern United States Cyrilla racemiflora, titi, 25 ft, southeastern United States Magnolia ashei, Florida bigleaf magnolia, 25 ft, northern Florida. Trees are deciduous, evergreen, or sometimes semi-evergreen, depending upon climate and species. A well-known tree indigenous to the southeastern United States is the southern live oak (Quercus virginiana), usually regarded as evergreen. In fact, this oak is not truly evergreen in the strict sense. As the new leaves emerge in the spring, the previous year’s leaves are lost, and the tree becomes essentially leafless for a short period until the new leaves have fully expanded. But some oaks are, indeed, perma- nently evergreen, such as Quercus myrsinifolia, Q. glauca, and Q. acuta—all from Japan. An- other well-known tree, Magnolia grandiflora, remains fully evergreen throughout the year. In this species, leaves normally remain on the tree for 2 years before falling in spring of the second year, but the tree is never leafless. Shrubs Typically, shrubs differ from trees primarily in being multitrunked from the base and shorter than trees. Shrubs are seldom more than 20 feet in height; some of the largest may be single- trunked and treelike. Stature alone is not an absolute measure of shrub classification. A good example is illustrated by Magnolia virginiana. The northern aspect of this species, distributed from Massachusetts to North Carolina, is typi- cally deciduous, multitrunked, and shrubby, with a spreading habit that fits the stature of a large shrub. In cultivation and in the wild, it sometimes attains a height of 30 feet but seldom more. The southern aspect, often referred to as var. australis, occurs from North Carolina to southern Florida and west to Tennessee, Arkan- sas, and southeastern Texas, where it becomes a lofty evergreen tree with one or two trunks and sometimes reaches 100 feet in height. In cultiva- tion, the southern plant consistently remains evergreen and treelike at least as far north as Washington, DC, even in the coldest winters. Although the distinction of deciduous or ever- green habit and the differences in stature can be used to separate the northern and southern aspects in the living state, no discernable taxo- nomic characters can be found to consistently distinguish these variants morphologically. Moreover, the two variants of M. virginiana are often intermediate as to evergreenness and stature, factors that further complicate their identification. For these reasons, var. australis is not recognized in this catalog as a distinct entity. Examples of common native and introduced shrubs cultivated in the southeastern United States include: Abelia < grandiflora, glossy abelia, 6-8 ft, a hybrid of Chinese parentage Agarista populifolia, pipe plant, 12-15 ft, southeastern United States Camellia japonica, common camellia, 20 ft, Japan Chionanthus virginicus, old-man's beard, 12 ft, eastern United States Kalmia latifolia, mountain laurel, 20 ft, eastern United States. Subshrubs A subshrub, or undershrub, is an intermediate category of a half-woody, or suffruticose, plant. The lower part of the stem, from which the new growth emerges each year, is woody and persis- tent. These are not simply half-hardy plants but represent a stage between herbaceous and the truly woody condition. Examples of subshrubs in the catalog include: Chrysanthemum nipponicum, Nippon daisy, Japan Indigofera spp., indigo (listed species) Lespedeza spp., bush clover (listed species) Nierembergia scoparia, tall cup-flower, Uruguay and Argentina Pachysandra procumbens, Allegheny spurge, southeastern United States Pachysandra terminalis, Japanese spurge, Japan, People's Republic of China, and Korea Teucrium chamaedrys, European germander, Europe Vinca major, greater periwinkle, Europe Vinca minor, common periwinkle, Europe. Woody climbers, or lianes The term scandent, from the Latin scandens, refers to woody and herbaceous plants that climb by various means. The term liana, or liane, refers to a woody climbing plant, especially in the tropics, but lianes occur in all climates except polar areas. Woody climbers include plants in five categories according to their mode of climb- ing, as follows: Root-climbers with holdfast roots and disc- like attachments Campsis radicans, trumpet vine, eastern United States Decumaria barbara, wood-vamp, southeastern United States . Euonymus fortunei, wintercreeper spindle- bush, Japan, People’s Republic of China, and Korea Hedera helix, English ivy, Europe Hydrangea anomala ssp. petiolaris, climbing hydrangea, Japan. Tendril-climbers with auxiliary filiform leaf- less and usually branched organs that attach to another body and curl around it for support Morphologically, a tendril may be a modified stem, a modified branch, a petiole, a stipule, or a leaflet of a compound leaf. Occasionally, as in Parthenocissus tricuspidata, the filiform branch tips are provided with terminal cups called holdfasts. Examples include: Ampelopsis arborea, peppervine, eastern United States Ampelopsis glandulosa var. brevipedunculata, porcelain-berry, Japan and People’s Republic of China Bignonia capreolata, cross vine, southeastern United States Parthenocissus quinquefolia, Virginia creeper, eastern United States Parthenocissus tricuspidata, Boston ivy, Japan and People’s Republic of China Vitis spp., grape vine. Twiners that climb spirally for support Actinidia arguta, tara vine, Japan, Korea, and northeastern Asia Actinidia deliciosa var. deliciosa, Chinese goose- berry or kiwi fruit, People’s Republic of China Akebia quinata, chocolate vine, Japan, People’s Republic of China, and Korea. Berchemia scandens, Alabama supplejack, eastern United States Celastrus orbiculatus, Oriental bittersweet, Japan, Korea, and People’s Republic of China Gelsemium sempervirens, Carolina jessamine, southeastern United States Kadsura japonica, kadsura vine, Japan, People’s Republic of China, with Taiwan Lonicera sempervirens, trumpet honeysuckle, eastern United States Trachylospermum jasminoides, Confederate jasmine, Japan, Korea, and People’s Republic of China Wisteria spp. (Species twine either to the right or left). Scramblers with long straggling branches that support themselves on other branches with- out fastening in any active manner; prickles or thorns may assist climbing, as in roses and brambles Rosa laevigata, Cherokee rose, People’s Republic of China Rubus calycinoides, Taiwan Rubus cockburnianus, People’s Republic of China. Leaf-petiole climbers that hold the stem in place by twining around an adjacent branch Clematis spp. and hybrids. Plant Nomenclature The guiding principles for the regulation of plant nomenclature are embodied in two contemporary documents: (1) the International Code of Botani- cal Nomenclature, 1988 edition (called the Botani- cal Code) and (2) the International Code of No- menclature for Cultivated Plants, 1980 edition (called the Cultivated Code). The Botanical Code “governs the use of botanical names in Latin form for both cultivated and wild plants, except for graft chimaeras” (Brickell et al. 1980: 11). The Cultivated Code regulates nomenclatural matters related exclusively to agricultural, horti- cultural, and silvicultural cultivars. Reasons for changing plant names are rooted in the rule of priority stated in Article 11 of the Botanical Code. For a genus, the correct epithet is the earliest legitimate one at the same rank, except for a conserved name (nomen conservan- duny; for example, Pseudolarix Gordon (1858) not Chrysolarix H.E. Moore (1965). In categories below the rank of genus, the correct name is the earliest legitimate name at the same rank— species, subspecies, varietas, or forma—to which the plant is assigned. A plant has only one correct name, generally a binary name or bino- mial, that consists of a genus name (for example, Magnolia) followed by a specific epithet (for example, grandiflora). To this binary name is appended the name of the authority(ies) who published the name. The correct citation of the southern magnolia is Magnolia grandiflora L. (“L.” stands for Carl Linnaeus, who first described this species in 1759). Other names for this plant are treated as synonyms (Magnolia foetida Sarg., for example) or homonyms but are illegitimate for purposes of scientific nomenclature. The binary name must be in Latin form regardless of its derivation. Plant nomenclature contains many names adapted from other languages, especially from Greek. Names of plants are based on nomenclatural types, usually type specimens, which are docu- mented, dried, and pressed specimens deposited in an herbarium for permanent reference. In the absence of a specimen, an accurate illustration may be substituted for purposes of typification. Botanical names published since 1935 must be accompanied by a Latin diagnosis to be botani- cally legitimate. Hierarchy of Rank Categories Genus Genus (plural, genera) is the first major taxo- nomic category under the family. The catalog is arranged alphabetically by genus, beginning with Abelia R.Br., assigned to the family Caprifoliaceae and its common name, honey- suckle family. Genera of Caprifoliaceae in the catalog include: Abelia, Diervilla, Dipelta, Heptacodium, Kolkwitzia, Lonicera, Sambucus, Symphoricarpos, Viburnum, and Weigela. Some families are monotypic, comprising a single genus, such as Ginkgo in the Ginkgoaceae and Cercidiphyllum in the Cercidiphyllaceae. For the convenience of the user, the species, subspecies, varietas, forma, and cultivar names are listed alphabetically under each genus without regard to botanical rank. A supplementary list (Appen- dix D) groups the names according to botanical rank. Species Biologically, the species is the basic taxonomic unit employed in the recognition and classifica- tion of plants. For purposes of this catalog, Cronquist’s general definition of species is useful: “Species are the smallest groups that are consis- tently and persistently distinct, and distinguish- able by ordinary means” (1988, p.71). Criteria for the recognition of species may include factors of reproductive isolation, chromosome number, phenetic or morphological discontinuity, geo- graphic isolation, and ecogeographic coherence. As the basic unit of biology, the species is subor- dinate to the genus. As the next higher major category, the genus consists of one or more species. The number of species varies from genus to genus. The monotypic genus Ginkgo, for example, consists of a single species, biloba, but the genus Quercus consists of many species, perhaps 450 worldwide, and some genera are even larger. While botanists argue the relative importance of species criteria, the viability of the species as a fundamental biological unit is attested by the presence of over 1,000 Linnean names in the catalog more than 200 years after the death of Linnaeus. — The word species is either singular or plural (specie refers to coinage). It is abbreviated sp. when singular and spp. when plural. In this catalog, species and cultivar names are cited in strict alphabetical order under the name of the genus. The entries under the genus Abelia, for example, include the species chinensis, followed by the cultivar ‘Edward Goucher’, the hybrid x grandiflora, and the cultivars ‘Prostrata’ and ‘Sherwoodii’. In horticultural works, authorities for cultivar names are not required according to the Culti- vated Code. In nursery lists and in many publi- cations on landscape plants, authorities for botanical names are usually omitted, but this is a mistake and leads to confusion. The citation of authorities clearly identifies the botanical name with its correct author(s), for example, Aesculus flava Solander, not of Aiton. In another example, the name Acer parviflorum was applied by Ehrhart in 1789 to A. spicatum Lamarck (1786) and later by Franchet & Savatier in 1879 to the plant now known as A. nipponicum Hara. Be- cause of Ehrhart’s earlier use of the specific epithet (though illegitimate because of Lamarck’s priority), the Franchet & Savatier name was a “later homonym” and therefore illegitimate. Without an author citation, a reference to the name A. parviflorum would not inform the reader whether A. spicatum or A. nipponicum was meant. Subspecies The subspecies, abbreviated ssp. or subsp., follows the rank of species and is often used to categorize geographic or ecological variants of a polymorphic species into generally disjunct morphological units. These units may be iso- lated from each other by latitude, longitude, altitude, and by ecological or geographical fac- tors, as well as by morphological characters. Botanists still disagree on the application of the subspecies category, especially when the distinc- tions among variants are ill defined. Examples of subspecies in the catalog include Acer negundo L. ssp. mexicanum (DC.) Wesmael, Hydrangea anomala D. Don ssp. petiolaris (Sieb. & Zucc.) McClint., and Koelreuteria elegans (Seemann) A.C. Sm. ssp. formosana (Hayata) F.G. Meyer. Varietas The category varietas, or botanical variety (abbre- _ viated var.) was long used as the only infraspe- cific category generally recognized by botanists. Because of difficulties in evaluating morphologi- cal characters in plants, the categories subspe- cies and varietas have been used interchangeably by different workers. There is no common agree- ment among botanists on the application of these categories. As indicated by Cronquist, “Nowa- days one taxonomist’s subspecies is likely to be another’s variety” (1988, p. 99). Varieties are recognized in many genera in this catalog. In the genus Acer, for example, we recognize Acer rubrum L. var. trilobum T. & G. ex K. Koch, A. rubrum L. var. drummondii (Nutt.) Sarg., A. palmatum Thunb. ex J.A. Murr. var. amoenum (Carr.) Ohwi, and A. saccharum Marsh. var. rugelii (Pax) Rehd. Forma The category forma (abbreviated f.) has long been applied to distinguish transitory variation with- out persistent biological significance that is found randomly within populations of wild plants. Such variation includes flower color, leaf size, leaf shape, plant habit, vesture (hairiness, for example), and other characters. The following examples illustrate the use of forma in three well- known native woody plants cultivated in the southeastern United States: pink flowering dogwood (Cornus florida L. f. rubra (Weston) Schelle), yellow-fruited flowering dogwood (Cornus florida L. f. xanthocarpa Rehd.), and the yellow-fruited American holly (Ilex opaca Ait. f. xanthocarpa Rehd.). Before the term cultivar was adopted by the Cultivated Code in 1953, the category forma had long been in use for many garden plants and also for some wild plants. Examples include Sophora japonica L. f. pendula (Sweet) Zabel and Pseudotsuga menziesii (Mirb.) Franco var. glauca (Beissn.) Franco f. glauca pendula Rueppel that were automatically given cultivar status after 1953. These plants are now properly cited as Sophora japonica L. ‘Pendula’ and Pseudotsuga menziesii (Mirb.) Franco var. glauca (Beissn.) Franco ‘Glauca Pendula’. Cultivar The 1980 edition of the Cultivated Code provides guidelines “to promote uniformity, accuracy, and fixity in the naming of agricultural, horticultural, and silvicultural cultivars (varieties).” The term cultivar (derived from cultivated variety) was included when the Cultivated Code was drawn up in 1953; it denotes “an assemblage of culti- vated plants which is clearly distinguished by any characters (morphological, physiological, cytological, chemical, or others) and which, when reproduced (sexually or asexually), retains its distinguishing characters.” Cultivars are without rank in the hierarchy of botanical nomenclature. In woody plants, culti- vars are usually perpetuated as clones, that is as a genetically uniform assemblage of plants derived originally from a single individual and reproduced asexually as cuttings, divisions, or grafts, or by obligate apomixis. Seed-reproduced cultivars occur infrequently among woody plants (for example, in Acer and Betula). They are, however, well known in herbaceous genera, for example, Impatiens, Phlox drummondii ‘Sternenzauber’, and Zea mays. Cultivar names, to be legitimate, must be regis- tered through the appropriate international registration authority or published with an adequate description in a recognized publication, such as a dated nursery catalog or journal. Cultivar names simply listed in a nursery catalog or other publication are without valid status. These practices are important for ensuring the validity and stability of cultivar names. Cultivar names published on or after January 1, 1959, may no longer be in Latin form but must be fancy names in the vernacular, that is, in English or another modern language. Cultivar names may be designated by the abbreviation cv. pre- ceding the name, or, as in this catalog, by single quotation marks as in the following examples: Abelia ‘Edward Goucher’, Hibiscus syriacus ‘Diana’, and Magnolia ‘Galaxy’. However, cultivar names in Latin form published before January 1, 1959, such as Acer palmatum ‘Atropurpureum’ and Ilex aquifolium ‘Argentea Marginata’, must be retained, according to the Cultivated Code. Our method of listing cultivar names alphabeti- cally facilitates easy identification of the binary name (Latin scientific name) associated with a cultivar name, especially in those genera for which the user of the catalog does not know the species of a particular cultivar. The following examples from the genus Acer illustrate the usual method of citing cultivars, first listing the cultivar name and, in square brackets, identify- ing the species: ‘Akaji Nishiki’ [A. palmatum Thunb. ex J.A. Murr.]: ‘Schwedleri’ [A. platanoides L.]: and ‘Temple’s Upright’ [A. saccharum Marsh.]. In some cases, the cultivar is identified only as to genus. Sexual hybrids In interspecific hybrids, a multiplication sign is placed before the hybrid epithet as in Abelia x grandiflora, a hybrid of A. chinensis and A. uniflora. In intergeneric hybrids, a multiplication sign is placed in front of the hybrid genus name as in * Cupressocyparis leylandii, a hybrid of Chamaecyparis nootkatensis and Cupressus macrocarpa. Graft chimeras As defined in the Cultivated Code, “Graft-chimae- ras are composed of tissues in intimate associa- tion from two different plants. They originate by grafting and are not sexual hybrids.” There is no combining of cell contents or nuclei as in the case of hybrids; thus the word hybrid is inappro- priate for these plants. In a graft chimera, the tissue of a shoot originating at the callus of the graft union contains at least one cell from the scion and one from the root stock. Periclinal chimeras, in which cells from the scion and cells from the stock are in different layers, are persis- tent when propagated. Chimeras may exhibit characters typical of the scion or the stock, or a range of intermediate forms. The graft chimeras listed in the catalog are of the periclinal type. Graft chimeras are most unusual in the simultaneous production of flowers from the scion and from the stock. They are known worldwide by only a very few well- documented examples; two are listed in the catalog, designated with a plus (+) sign before the name, as follows: ¢ Camellia +‘Daisy Eagleson’ = C. sasanqua ‘Maiden’s Blush’ + C. japonica. Camellia sasanqua ‘Maiden’s Blush’ is the rootstock and C. japonica, the scion. At flowering time, this evergreen shrub displays simultaneously on different branches the single flowers of C. sasanqua and the semi-double flowers of C. Japonica. @ +Laburnocytisus adamii = Cytisus purpureus + Laburnum anagyroides. This small deciduous tree combines species of two genera of the bean family (Fabaceae). Branches of the yellow flowers of L. anagyroides and the dull purple flowers of C. purpureus bloom simultaneously on the same plant. How Plant Names Change The names of plants are not fixed in time but are subject to change for various reasons. It is not difficult to find examples of plants long known under established names that are incorrect according to the Botanical Code. Name changes for some well-known woody landscape plants listed in the catalog are discussed below. The name Plumbago auriculata Lam. is the correct binary name for a now widely cultivated South African species. Published by Lamarck in 1786, this name has an 8-year priority over the name Plumbago capensis Thunb. that was long used for this plant. In another example, the name Cladrastis lutea (Michx.f.) K. Koch dates from 1813 and is well known; but in 1811 Dumont de Courset had published the specific epithet kentukea for the same plant. According to the rule of priority, the name Cladrastis keentukea (Dum.-Cours.) Rudd has date priority as the correct name for yellow-wood. Changes in plant names sometimes may not conform with the facts, causing more confusion than existed before the change was made. Two examples illustrate name changes too hastily made. Under Magnolia in Hortus Third (Bailey 1976), the entries M. heptapeta (Buc’hoz) Dandy and M. quinquepeta (Buc’hoz) Dandy are listed for two well-known magnolias, M. denudata and M. liliiflora, respectively. In 1779, Buc'hoz pub- lished Lassonia heptapeta and L. quinquepeta for these taxa. In 1934, Dandy transferred the Buc'hoz epithets to the genus Magnolia. Ina paper by F. G. Meyer and E. McClintock pub- lished in 1987, the evidence shows that the combinations of Dandy were totally misapplied and without botanical validity. The original Chinese illustrations on which these names were based are artist’s renditions, probably of Magno- lia, but the details are totally incorrect and the drawings may not be properly assigned to the genus Magnolia or, indeed, to any known living plant. Meyer and McClintock concluded that the earliest valid names for these magnolias, M. denudata and M. liliiflora, were correctly pub- lished by Desrousseaux in 1791 and stand as the correct names for these plants. The name Toona sinensis (Endl.) M.J. Roem. applies to a tree native to eastern Asia, replacing the name Cedrela sinensis Juss. This follows an earlier taxonomic decision that the name Toona should apply to the Asiatic species, while the New World species (although closely related) are correctly placed in the genus Cedrela. Until relatively recently, two species of Sequoia were recognized. A detailed study by J.T. Buchholz showed that only the coast redwood (Sequoia sempervirens (D. Don) Endl.) should be retained in the genus, while the giant sequoia of the high Sierras of California (formerly known as Sequoia gigantea Lindl.) belongs to the closely related genus Sequoiadendron with the binary name Sequoiadendron giganteum (Lindl.) J. Buchholz. From time to time, various specific epithets have been applied to the Douglas fir—including Pseudotsuga douglasii Carr. (1867), P. lindleyana Carr. (1868), P. taxifolia (Lamb.) Britton (1889), and P. mucronata (Raf.) Sudworth (1895). But all of these must give way to the name Pseudotsuga menziesii (Mirb.) Franco (1950), based on Pinus menziesti Mirb. (1825), as the valid name for this well-known tree of the western United States. A well-known tree indigenous to the southeast- ern United States, the yellow buckeye, should be cited as Aesculus flava Sol. (1784), not A. flava Ait. (1789). This may appear as a small detail, but it illustrates the application of the rule of priority that exists to promote stability and accuracy in plant nomenclature. The name A. octandra Marsh. (1785), published later and long used for this tree, is a synonym without taxo- nomic validity of A. flava Sol. Confusion reigns in the names applied to two evergreen shrubs planted in the southeastern states, one of them commonly grown and the other one rare. The well-known Florida native Illicitum parviflorum Michx. ex Vent. is often misidentified in nurseries as I. anisatum L., a Japanese plant. Although the Japanese species is barely known in most areas, its name has long been associated with the wrong plant. Another common shrub in nurseries, and one widely cultivated in the southeastern United States, is Ternstroemia gymnanthera (Wight & Arn.) Sprague of the tea family (Theaceae). It has long been sold in nurseries under the name Cleyera japonica Thunb., a different though closely related plant. Many nurseries are now aware of the correct identification of these plants and are labeling them accordingly. The true Cleyera japonica is an attractive, small evergreen tree with fragrant white flowers and black fruit, but it is rarely cultivated. The name Anisostichus capreolatus (L.) Bur. (1884) can no longer be used for the cross vine, because the earlier name Bignonia capreolata L. 9 (1753) is a nomen conservandum, or conserved name, for this woody climber of the southeastern United States. For more than a century, nurseries confused two commonly planted species in the genus Ligustrum—L. japonicum Thunb., Japanese privet: and L. lucidum Ait.f., wax-leaf privet. The name L. lucidum was misapplied to the Japanese privet, while the name L. japonicum was mistakenly applied to the wax-leaf privet. These errors were repeated year after year in nursery catalogs until Roland Jefferson (1976) corrected them. The problem was a simple case of applying the right name to the right plant. Homonyms According to the Botanical Code, “A name, unless conserved (Art. 14) or sanctioned under Art. 13.1(d), is illegitimate if it is a later homonym, that is, if it is spelled exactly like a name based on a different type that was previously and validly published for a taxon of the same rank.” Many homonyms exist among plant names found in the literature. For example, Linnaeus in 1753 pub- lished Ilex aquifolium as the name for English holly (in the Aquifoliaceae, or holly family). In 1784, Thunberg used Ilex aquifolium for a Japa- nese plant subsequently recognized as being in the Oleaceae, or olive family. Placing the Japa- nese plant in the genus Osmanthus of the Oleaceae, Siebold in 1846 adopted the specific epithet from Thunberg's name and published Osmanthus aquifolium. But this name is illegiti- mate, because Thunberg's name is a later hom- onym, and the nomenclatural type for Ilex aquifolium is the English holly named by Linnaeus. Because the earliest available specific epithet for the Japanese plant is that from G. Don's Ilex heterophylla (1832), the legitimate name for the familiar holly olive is Osmanthus heterophyllus (G.Don) P.S.Green var. heterophyllus. Another significant confusion occurred in the names of two well-known species in the genus Rhododendron, one an elepidote rhododendron and the other a deciduous azalea. In 1826, Blume applied the name Hymenanthes japonica to the elepidote rhododendron. In 1835, Siebold and Zuccarini transferred the name Hymenanthes to Rhododendron as a generic synonym and named the species in question Rhododendron metternichii Sieb. & Zucc.; however, by citing the earlier name H. japonica Blume as a synonym they rendered R. metternichii illegitimate. In 1909, Camillo Schneider transferred the earlier 10 name Hymenanthes japonica Blume to Rhodo- dendron japonicum (Blume) Schneider. This was, in fact, the correct name until very recently the Committee for Spermatophyta of the Interna- tional Botanical Congress determined that the specific epithet japonicum correctly applies to the deciduous azalea. The name R. degronianum ssp. heptamerum (Maxim.) Hara is now the correct name for the elepidote rhododendron long known as R. metternichii. The illegitimate name R. metternichii Sieb. & Zucc., however, continues to be used widely in horticultural circles. The deciduous azalea involved in this confusion of names was described by Asa Gray as Azalea japonica, in the Luteum subseries from Japan. In 1908, Suringar transferred the specific epithet to Rhododendron as R. japonicum (A.Gr.) Suring. Suringar’s publication of this combination was, however, interpreted by the author of a revision of the genus as provisional, making the name illegitimate as applied to the azalea and requiring its use for the elepidote rhododendron. Because the resulting name changes would have undesir- able consequences, a formal proposal was made to reject R. japonicum (Blume) Schneider. After detailed re-examination of Suringar’s work, the Committee for Spermatophyta concluded that the Suringar combination (using japonicum for the azalea) was indeed validly published. The name R. japonicum (Blume) Schneider for the elepidote rhododendron is therefore illegitimate as a later homonym and the proposal to reject became moot. As noted, a later homonym may be conserved by formal action under the Botanical Code. For example, the genus name, Torreya Arn. (1838) of the yew family (Taxaceae) is conserved, and the earlier homonym Torreya of Rafinesque (1818) applied to a plant in the mint family (Lamiaceae) is rejected. Synonyms Many plants have been repeatedly redescribed by different botanists, thus creating a long, compli- cated synonymy that is often difficult to recon- cile. The synonyms of Magnolia denudata Desr. (1791), for example, include M. conspicua Salisb. (1806), M. precia Correa ex Vent. (1803), and M. yulan Desf. (1809). The name Negundo fraxinifolium de Vos (1887) isa synonym and invalid, because its nomenclatural type is the same as that of Acer negundo L. (1753), boxelder, a common North American tree that spans the continent east to west and is cultivated world- wide. Common taxonomic synonyms are listed in the catalog to identify invalid names found in nurs- ery catalogs and in the horticultural and botani- cal literature, such as the following: Cladrastis lutea’ (Michx.f.) K. Koch = C. kentukea (Dum.-Cours.) Rudd Magnolia foetida (L.) Sarg. = M. grandiflora L. Rhododendron nudiflorum (L.) Torr. = R. periclymenoides (Michx.) Shinners Rhododendron metternichii Sieb. & Zucc. = R.degronianum Carr. ssp. heptamerum (Maxim.) Hara Rhododendron roseum (Loisel.) Rehd. = R. prinophyllum (Small) Millais. Vernacular (Common) Names The botanical (Latin-form) names and registered cultivar names of plants have universal applica- tion in the world scientific community. They are, moreover, instructive in many ways. By con- trast, vernacular names are simply names of convenience for local application. Over a wide area some plants may have several common names, all of equal value, as in laurel magnolia, bay, sweet bay, swamp bay, beaver tree, and laurel for Magnolia virginiana. Some plants, especially the exotics, are often without a com- mon name until one is invented. In this catalog we include one or two common names in general use for many of the listed plants. These names are summarized in Appendix E. While there are problems associated with com- mon names, many people prefer the vernacular. Some complain about Latin names of plants as too awkward and difficult to pronounce. Ap- proached with an open mind, scientific names are not difficult. Familiar names used in the vernacular, such as anemone, catalpa, chrysan- themum, gladiolus, iris, magnolia, petunia, phlox, rhododendron, sassafras, wisteria, yucca, and zinnia are, in fact, Latin genus names that have entered vernacular usage. Once established, common names are often useful and convenient for trees such as Douglas fir, deodar cedar, white oak, and American elm. However, unlike botanical names, common ‘names are sometimes misleading and confusing and may impede clear communication and understanding, since nothing about these names relates to name stability or to classification. In the southeastern United States, for example, the native deciduous azaleas are commonly known as “honeysuckle,” but to many people honey- suckle refers only to species of Lonicera of the honeysuckle family (Caprifoliaceae). The com- mon name for Rhododendron periclymenoides is pinxterbloom in Maryland, purple honeysuckle in the Carolinas, and election pink in some other areas of the southeast. In the United States, the indigenous species of Tilia are called basswood or linden, while in the United Kingdom members of this genus are called lime trees. The use of common names should be discouraged because of the endless possibilities for misidentification and confusion. Symbols and Abbreviations Acronyms are cited alphabetically under each plant entry to identify the collection sites, for example, DCNA = District of Columbia/National Arboretum; FLUF = Florida/University of Florida, Gainesville; and GAUG = Georgia/University of Georgia. Cultivar names are spelled with initial capital letters in roman type and are enclosed with single quotation marks: Abelia ‘Edward Goucher’, Magnolia ‘Galaxy’. Other symbols and abbreviations follow. ssp. = subspecies: Hydrangea anomala D. Don ssp. petiolaris (Sieb. & Zucc.) McClint. var. = varietas (botanical variety): Acer palmatum Thunb. ex J.A. Murr. var. amoenum (Carr.) Hara x = multiplication sign used for hybrids: interspecific hybrids are identified with the multiplication sign placed in front of the hybrid epithet, as Abelia < grandiflora (Andre) Rehd.; in bigeneric hybrids the multiplication sign is placed in front of the hybrid genus name, as * Cupressocyparis leylanditi (Dallim. & Jacks.) Dallim. + = symbol for graft chimera, as Camellia +‘Daisy Eagleson’ [] enclose botanical names of cultivars and names of parents of hybrids and cultivars * designates plant introductions from the U. S. National Arboretum breeding program ? indicates uncertainty as to parentage. 11 ABELIA ABELIA R.Br. CAPRIFOLIACEAE Honeysuckle Family (Contributed by T. R. Dudley) chinensis R.Br. Chinese A. DCNA MDFM SCWI ‘Edward Goucher’ [A. < grandiflora < A. schumannii] ALBH GAUG SCCU TXRS GAJS MDGC TNFN < grandiflora (Andre) Rehd. Glossy A. [A. chinensis < A. uniflora] DCCG MDJH MSEP NCSM FLMG MDKN NCBE SCCU LASL MDLT NCDU TNBM MDDF MDNA NCGP ‘Prostrata’ [A. < grandiflora (Andre) Rehd.] [A. chinensis < A. uniflora] DCNA ‘Sherwoodii’ [A. < grandiflora (Andre) Rehd.] [A. chinensis < A. uniflora] GAUG SCBR ABELIOPHYLLUM Nakai OLEACEAE Olive Family distichum Nakai White Forsythia DCNA MDLT ABIES UMiill. Fir PINACEAE Pine Family a ae a alba Mill. Silver F. GABS NCTE VAWP balsamea (L.) Mill. Balsam F. DCNA brachyphylla Maxim. = A. homolepis cephalonica Loud. Greek F. DCNA MDLT 12 ABIES chensiensis Tieghem ssp. salouenensis (Bord.-Rey. & Gaussen) Rushforth Shensi F. DCNA cilicica (Ant. & Kotschy) Carr. Cilician F. VAMP concolor (Gord. & Glend.) Lindl. ex Hildebr. White F. MDLT NCBE VAMP ernestii Rehd. = A. chensiensis ssp. salouenensis firma Sieb. & Zucc. Momi F. ALOS MDLT TNWF DCNA NCBE fraseri (Pursh) Poir. Fraser F. NCAS TNBV VAFR VASG ‘Glauca’ [A. pinsapo Boiss.] DCNA holophylla Maxim. Manchurian F. DCNA homolepis Sieb. & Zucc. Nikko F. DCNA homolepis Sieb. & Zucc. var. umbellata (Mayr) Wils. = A. xumbellata koreana Wibls. Korean F. DCNA nobilis (Doug]l.) Lindl. = A. procera nordmanniana (Steven) Spach Nordmann F. DCAE MDLT NCBE NCKK VABF numidica de Lannoy ex Carr. Algerian F. DCNA pectinata DC. = A. alba pinsapo Boiss. Spanish F. DCSH VAMP ABIES procera Rehd. Noble F. DCNA SS WS BSDy FOTHERGILLA major (Sims) Lodd. [illustrator Susan M. Johnston] | } FRAXINUS pubescens Lam. = F. pennsylvanica sieboldiana BI. . DCNA VATA toumeui Britton = F. velutina velutina Torr. var. coriacea (S.Wats.) Rehd. Leatherleaf A. FLUF SCCU velutina Torr. var. glabra Rehd. Modesto A. FLMM FLUF FLWG GALPHIMIA Cav. MALPIGHIACEAE Malpighia Family SS EEE IO Tn ee Soe SE | glauca Cav. ALBG FLUF GACG SCWI GARDENIA Ellis RUBIACEAE Madder Family a ST REDE 1) ES DE EON eR SL NC aE ST] jasminoides Ellis Cape Jasmine FLMG GATS NCWC VACM LAAL LARP LAHG MSMN jasminoides Ellis var. radicans (Thunb.) Makino = ‘Radicans’ ‘Radicans’ [G. jasminoides Ellis] LAHG LARP MSMN VANB GAULTHERIA L. ERICACEAE Heath Family procumbens L. Wintergreen, Tea Berry DCNA GAYLUSSACIA HBK. ERICACEAE Huckleberry Heath Family baccata (Wang.) K.Koch Black H. VATG brachycera (Michx.) A.Gr. GINKGO GELSEMIUM Juss. Jessamine LOGANIACEAE Logania Family ae oe TN SV Ne RO PS ‘Plena’ [G. sempervirens (L.) Ait.f.] = ‘Pride of Augusta’ ‘Pride of Augusta’ [G. sempervirens (L.) Ait.f.] Double-flowered Jessamine ALTD VACW VAPH LASL VAGS rankinii Small SCWI VACW sempervirens (L.) Ait.f. Yellow J., Carolina J. ALON LAHG TNCG VAWM ARPT LASL VACW VAWR ARSN NCOP VAGG GAEC SCBR VAGS GENISTA L. Broom FABACEAE (Faboideae) Bean Family RT ave POEL EAS SSD Be OE TT TD lydia Boiss. VACW ‘Prostrata’ [G. germanica L.] DCNA GINKGO L. GINKGOACEAE Ginkgo Family PLS Be DO SS ae eS ER sO EO LE biloba L. Maidenhair Tree, Ginkgo DCCG LASL NCDU VABF DCWH MDHN NCTE VAMP FLCG MDJS TNCT VATA GAGN MSMN TNFE VAWR GAMW NCCA TNPW (The specimen at GAGN develops pendent mammillate projections (called “chi” in Japan) from the lower side of the main branches; this is the first specimen of its kind recorded in the United States.) ‘Fastigiata’ [G. biloba L.] GACD ‘Lakeview’ [G. biloba L.] TNPW ‘Mayfield’ [G. biloba L.] TNPW i GLEDITSIA GLEDITSIA L. Honeylocust FABACEAE (Caesalpinioideae) Bean Family |e Sa a at eT a co DS SON EE So RSE EEO ee ee de a en ey aquatica Marsh. Water Locust DCLC japonica Mia. Japanese H. SCCU ‘Shademaster’ [G. triacanthos L. f. inermis (Pursh) Schneid.] NCDU ‘Sunburst’ [G. triacanthos L. f. inermis (Pursh) Schneid.] NCCA TNSC VACW triacanthos L. Common H. MDHN MDJH VACW triacanthos L. f. inermis (Pursh) Schneid. Spineless H. ALBH NCCA TNBO GLOCHIDION J.R. &J.G.Forst. EUPHORBIACEAE Spurge Family (ES SE a a A Ee puberum (L.) Hutch. FLUF GLYCOSMIS Correa RUTACEAE Citrus Family citrifolia (Willd.) Lindl. FLUF parviflora (Sims) Little = G. citrifolia GLYPTOSTROBUS Endl. TAXODIACEAE Taxodium Family heterophyllus (Brongn.) Endl. = G. lineatus lineatus (Poir.) Druce Chinese Water-pine DCNA MDBG pensilis (Staunt.) K.Koch = G. lineatus HALESIA GORDONIA Ellis THEACEAE Tea Family alatamaha Sarg. = Franklinia alatamaha axillaris (Roxb. ex Ker-Gawl.) D.Dietr. FLUF GACG chrysandra Cowan FLUF lasianthus (L.) Ellis Loblolly Bay ALAU SCBR VATA DCNA VANB GREWIA lL. TILIACEAE Linden Family eS a Sa LE ES biloba G.Don GAIS VABF GYMNOCLADUS Lam. FABACEAE (Caesalpinioideae) Bean Family dioica (L.) K.Koch Kentucky Coffee-tree DCCG DEMC VACW } VAMF DCNA MDHN VAGW DCPP MDJS VAHC HALESIA Ellis ex L. Silverbell Tree STYRACACEAE Storax Family carolina L. ALEH MDCA NCTE VACP DCCG MDGJ NCTP VAMP GARW MDJH SCBR VATA GASM MDJS SCWI VAWR GATS MDWP TNMB LALG MSMN TNSC MDBG NCAK TNSM diptera Ellis DCNA LAAL LASL NCTE FLMG LAHG MSMN TXLL GAEC LALG NCBE diptera Ellis var. magniflora Godfrey DCNA FLMG NCBE monticola Rehd. & Sarg. = H. carolina parviflora Michx. ALEH HALESIA carolina L. [illustrator Susan M. Johnston] res HALESIA ‘Rosea’ [H. carolina L.] DCNA tetraptera Ellis = H. carolina tetraptera Ellis var. monticola (Rehd.) Reveal & Seldin = H. carolina HALIMODENDRON Fischer ex DC. FABACEAE (Faboideae) Bean Family EE Ta OP NO A ES SP TS ITD halodendron (L.) Voss DCNA HAMAMELIS L. Witch Hazel HAMAMELIDACEAE Witch-hazel Family CR aT ET EOL ORT SRE OE a] arborea Ottol. = H. japonica ‘Arnold Promise’ [H. < intermedia Rehd.] [H. japonica = H. mollis} DCNA MDBG ‘Brevipetala’ [H. mollis Oliv.] DCNA MDBG MDKN ‘Carnea’ [H. vernalis Sarg.] MDBG ‘Christmas Cheer’ [H. vernalis Sarg.] MDBG ‘Copper’ [H. vernalis Sarg.] MDBG ‘Copper Beauty’ [H. X intermedia Rehd.] = ‘Jelena’ ‘Feuerzauber’ [H. < intermedia Rehd.] [H. japonica < H. mollis] DCNA ‘Fire Charm’ [H. X intermedia Rehd.] = ‘Feuerzauber’ X intermedia Rehd. [H. japonica < H. mollis] DCNA MDGC MDKN xjapollis J.Lange = H. xintermedia japonica Sieb. & Zucc. DCNA MDBG MDFM MDKN HAMAMELIS japonica Sieb. & Zucc. f. flavopurpurascens (Makino) Rehd. DCNA MDBG MDKN ‘Jelena’ [H. < intermedia Rehd.] [H. japonica < H. mollis] DCNA MDBG ‘Lombarts Weeping’ [H. vernalis Sarg.] DCNA MDBG MDFM ‘Luna’ [H. X intermedia Rehd.] [H. japonica < H. mollis] DCNA MDBG macrophylla Pursh = H. virginiana ‘Magic Fire’ [H. intermedia Rehd.] = ‘Feuerzauber’ mollis Oliv. Chinese W.H. ALBG DEMC MDBG DCNA GAUG MDKN ‘Orange Beauty’ [H. < intermedia Rehd.] [H. japonica < H. mollis] DCNA ‘Pallida’ [H. < intermedia Rehd.] [H. japonica < H. mollis] MDBG ‘Primavera’ [H. < intermedia Rehd_] [H. japonica = H. mollis] DCNA ‘Rubra’ [H. X intermedia Rehd.] [H. japonica < H. mollis] DCNA ‘Ruby Glow’ [H. < intermedia Rehd.] [H. japonica < H. mollis] (Sometimes listed as ‘Adonis’ DCNA MDBG ‘Sandra’ [H. vernalis Sarg.] MDBG vernalis Sarg. DCNA MDKN MDWP vernalis Sarg. f. tomentella Rehd. = H. vernalis vernalis Sarg. var. tomentella (Rehd.) Palm. = H. vernalis ‘Vesna’ [H. , LS ASA Lis Y rs utateaee NN yw 4 (; SCHIZOPHRAGMA hydrangeoides Sieb. & Zucc [illustrator Susan M. Johnston] SESBANIA SESBANIA Scop. FABACEAE (Faboideae) Bean Family drummondii (Rydb.) Cory SCWI punicea (Cav.) Benth. LAAL NCEG SCMP LASL SCBR SCWI tripetii (Poit.) F.T.Hubb. = S. punicea SEVERINIA ‘Tenore ex Endl. RUTACEAE Citrus Family buxifolia (Poir.) Tenore Chinese Box Orange FLCG FLUF FLMG GAJI LAAL VACW SHIBATAEA Makino ex Nakai POACEAE Grass Family kumasaca (Zoll.) Makino NCBE SINARUNDINARIA Nakai POACEAE Grass Family murielae (Gamble) Nakai = Thamnocalamus spathaceus nitida (Mitf.) Nakai DCNA SIPHONOSMANTHUS Stapf OLEACEAE Olive Family delavayi (Franch.) Stapf ALTD MDJW SKIMMIA Thunb. Skimmia RUTACEAE Citrus Family ‘Fisheri’ [S. japonica Thunb.] DCNA SOLANUM