Establishing Traditions at the

Stephen A. Spongberg

Charles Sprague Sargent’s early planting schemes and the collections he developed still form the backbone of the Arboretum today

Sargent and the Arboretum’s Beginnings devotions: one to trees and the development On the twenty-fourth of November, 1873, of the Arnold Arboretum, the other to his wife was appointed direc- and their enduring family life at Holm Lea, tor of the recently established Arnold Arbore- their home in Brookline, Massachusetts. tum by the President and Fellows of Harvard When Sargent accepted the directorship of College. On the twenty-sixth of November, he the fledgling Arboretum, he was also director married Mary Robeson of . Within the of the now-defunct Harvard Botanic Garden space of two days, Sargent’s life was forever in Cambridge and professor of horticulture at changed and set on a new course. The thirty- Harvard’s Bussey Institution. The latter two-year-old Bostonian had committed him- department was located on land in the self to what would soon become two lifelong Jamaica Plain section of Boston, which Ben- jamin Bussey had bequeathed to Harvard Col- lege on his death in 1842, the year that , Sargent’s friend and professional men- tor, had come to Harvard and the Botanic Garden in Cambridge. When James Arnold, a wealthy businessman and philanthropist from New Bedford, Massachusetts, died in 1868, he left a portion of his residual estate to three trustees and thereby set in motion the series of events that would result in the establish- ment of another Harvard-affiliated botanical institution. After Arnold’s trustees had com- pleted their negotiations with the Harvard Corporation, they agreed that the Arnold bequest would be transferred to the perma- nent trusteeship of the Corporation and that the income would be utilized for the estab- lishment and support of an arboretum, to be known as the Arnold Arboretum. With a small income from the trust to Charles Sprague Sargent, the first director of the Ar- devote to the Arboretum’s and nold Arboretum, studies pine cones m the Arbore- development tum’s collection. Photograph, taken in 1912 by T. E. 137 acres of the Bussey estate to use as its site, Marr, from the Archives of the Arnold Arboretum. Charles Sargent was faced with the task of 12

bringing together a living collection of plants Botanic Garden. As Gray’s protege, Sargent from all accessible corners of the earth for had been introduced to the network of Ameri- trial in the new Arboretum. The indenture of can botanists and naturalists who turned to the institution, which had been drawn up and Gray as the ultimate botanical authority in agreed upon by Arnold’s trustees and the Har- North America. By means of letters of vard officials, clearly outlined the purpose of introduction and by virtue of his stature as the first university-affiliated arboretum. Both dean of American botanists, Gray also parties hoped to see a comprehensive collec- provided Sargent with an entree into European tion of trees established that would stand as botanical and horticultural circles. On their a living museum. Specifically, the indenture honeymoon trip the Sargents sailed to stated that "as far as is practicable, all the and traveled on the Continent, where trees, shrubs, and herbaceous plants, either they were cordially welcomed to Europe’s indigenous or exotic, which can be raised in botanical gardens and museums, and where the open air..." would be grown, and this all- the foundations of many lifelong friendships encompassing collection should "be raised or with European plantsmen were laid. collected as fast as is practicable....";’ Basing himself initially in the estate office With this overwhelming responsibility, it is at Holm Lea, Sargent launched into a in retrospect astounding that anyone was will- prolonged planning phase for the Arboretum ing to undertake the directorship. Yet Sargent after returning from Europe in 1874. His first was ambitious and eager to begin the experi- step was to inventory the trees that were grow- ment. Wisely, and undoubtedly with approba- ing naturally on the topographically diverse tion from Professor Gray in Cambridge, Jamaica Plain property. These trees ranged Sargent immediately narrowed his focus to from the native hemlocks on Hemlock Hill, include only ligneous taxa-trees, shrubs, and then known as Bussey’s woods, to the native woody climbers-plants that would be the stands of oak and hickory woodlands that had expected emphasis if the young institution survived on several of the glacial drumlins, was to develop into an arboretum, which is sites that in earlier years had proven inap- by definition a place grown with trees. propriate for Bussey’s fields or orchards. Moreover, a rationale for this early policy deci- sion was based on the fact that the seven-acre The Early Development of the Living Botanic Garden in Cambridge comprised col- Collections lections of herbaceous plants systematically The trees and shrubs native to New England arranged in family beds. What the University but not indigenous to the Arboretum proba- clearly needed was a collection of ligneous bly constituted Sargent’s first list of desider- plants to complement the collections in Cam- ata. Exotic species growing in the Botanic bridge. Duplication of effort would result if Garden in Cambridge were also propagated for the Arboretum focused on herbaceous plants, establishment in Jamaica Plain and were and the space required for establishing plan- among the first accessions to be planted in the tations of trees was available at the Jamaica Arboretum. The early records indicate that Plain site, not in Cambridge. Sargent began an active correspondence with Fortunately, Sargent had not only the back- the curators of European botanical gardens ing of Asa Gray in this early departure from and nurserymen in England, France, and Ger- the letter of the law, but also his respect and many, and many of the species long cultivated friendship. As the foremost American botanist in Europe were thus established in the Arbore- of his generation and for thirty years the direc- tum nurseries for eventual transfer to the tor of the Botanic Garden, Gray had inaugu- Arboretum grounds. rated Sargent’s botanical and administrative Sargent’s real emphasis during the first two career when he engineered the young Brah- decades of his directorship, however, was on min’s appointment as his successor at the gathering a collection of native American 13

extremely wide range of trees and shrubs from every region of the and Canada were soon incorporated into the Arboretum’s living collections. Sargent had the assistance of a cadre of highly capable correspondents across North America in his census work, and hundreds of pleas for seeds of locally common as well as little-known species, many of nar- row range, accompanied his steady stream of requests for data on the forest resources of var- ious regions. Among his correspondents were such great botanists, plantsmen, and A view of the elm collection on the slope of Bussey naturalists as in Missouri, Hill in the Arnold Arboretum, illustrating Sargent’s Charles Mohr in Alabama, Michael S. Bebb plan to include native trees in the collection as in- in Illinois, Thomas Meehan in Pennsylvania, dividual specimens and as groups, in order to approx- John Muir in California, Cox m Loui- imate forest conditions. Photograph, taken in 1903 Reginald by T E Marr, from the Archives of the Arnold Ar- siana, and John Harbison in North Carolina. boretum. Due to their tireless efforts coupled with Sar- gent’s, the living collections of the Arnold Arboretum began to become comprehensive trees and shrubs. Indeed, the diversity of in scope. American species was to form the backbone Encouraged by the results of his census of the collection; Sargent based his planting work, Sargent began work on a natural exten- plan for the collection he intended to obtain sion of the project, and by 1890 a prospectus on the number of taxa known from North for his Silva of North America announced America and allocated space for each genus that this monumental undertaking would be and family accordingly. In this work Sargent published complete in 12 quarto volumes and was again indebted to the influence of Asa illustrated with 600 plates. After the twelfth Gray, who had recommended that he be given volume had appeared in as many years, the responsibility of preparing a census report however, two supplementary volumes were of North American trees for the United States announced, which were needed to accommo- government. date new species (primarily hawthorns) that Prior to Sargent’s benchmark contributions had been discovered during the course of the to the Tenth Census of the United States work. (embodied in his Report on the Forests of North America), information concerning the Acquisitions from Overseas extent, condition, and species composition of Sargent was occupied for more than a decade American forests was largely conjectural. A in the preparation of the Silva but still found study of forests of the scope of Sargent’s had time to stay abreast of botanical developments never before been undertaken, and no compre- overseas, and he took every opportunity to hensive flora of North America, let alone of broaden his network of correspondents to the United States, had been published. But include botanically inclined residents of for- having a governmental appointment and the eign lands. By 1878 this network had been ability to travel the length and breadth of the enlarged to include William Smith Clark on North American continent with a view to col- the northern Japanese island of Hokkaido. In lecting information, specimens, seeds, and 1882 correspondence was inaugurated with cuttings for propagation, Sargent gathered a Emil Bretschneider, a Russian physician who massive amount of pertinent data. As an was stationed in Peking (Beijing), and during indirect result of these activities, an the last decade of the nineteenth century Sar- 14

gent was posting letters to , son, who had completed two expeditions in an Irishman employed by the Chinese central and western China for the English Imperial Maritime Customs Service and liv- nursery firm of Veitch, agreed to undertake a ing in Ichang, a town on the banks of the third expedition, this one under Arboretum Yangtze River in Hupeh (now Hubei) Province auspices. of central China. Wilson’s exploits on all four of his Chinese With much of his personal field work in the expeditions-the fourth, in 1910-11, was also forests of North America completed, Sargent sponsored by the Arboretum-are well known turned to eastern Asia as the next region he in the annals of and horticulture. Not meant to explore in his continuing quest for incidentally, they had an enormous impact on woody plants to stand trial as cultigens in the the living collections of the Arnold Arbore- Arnold Arboretum. This decision was based tum. Quantities of propagation material of in part on the successful acclimation of many new plants arrived in Jamaica Plain Arboretum plants that had been grown from from China, and the onus fell to the green- seeds sent by his Asiatic correspondents. The house staff to coax the seeds to germinate and new direction was also based on Sargent’s the cuttings to root. Confronted with theoretical knowledge of the close unknown material whose germination and phytogeographical relationship between the cultural requirements had to be determined floras of eastern Asia and eastern North by trial and error, Jackson Dawson and his America, a biogeographic phenomenon that crew in the greenhouse had results as excep- had first been fully investigated by Asa Gray tionally fine as Wilson’s in the field. in the middle of the nineteenth century. When Wilson’s plants needed to be moved Although Sargent traveled to Japan in 1892, from the nurseries into the permanent collec- personally surveying Japanese forests and tions, Sargent was faced with the fact that cer- making extensive collections of seeds and tain groups had not been allocated sufficient specimens, he did not visit China until he was space in the overall Arboretum planting plan. in his sixty-second year. In 1903 he undertook The problem was that the Chinese and other a world tour but spent only brief periods in Asian species of many groups had not been China, , and Japan. Sargent returned to known when the planting plan, following the Boston, however, fully aware that he per- Bentham and Hooker classification, was sonally would be unable to undertake the devised, and Sargent and Frederick Law time-consuming and arduous field work Olmsted had been unable to anticipate the necessary to begin to understand and cata- floristic wealth of central and western China. logue the ligneous flora of the Chinese But Wilson’s bountiful harvest was too good empire. John Jack, Sargent’s right-hand man to be wasted, and exceptions to the original at the Arboretum, traveled to eastern Asia in planting rules had to be made to accommo- 1905, and as Sargent had before him, he date the many new species that required test- returned to the Arboretum with seeds and ing in Boston’s climate. One parcel of land, specimens of many Asiatic species never which had recently been added to the Arbore- before cultivated in North America. tum acreage on the south-facing slope of Bus- sey Hill, was given over to many of Wilson’s ’s Expeditions Chinese plants and is known today as the to China Chinese Walk. In 1907 Sargent was finally successful in finding an explorer and naturalist who had Sargent and Rehder Document the Col- previously proven his worth as a collector in lections the Middle Kingdom and was willing to While Charles Sargent was aggressively undertake additional botanical and horticul- developing the living collections during the tural exploration in China. Ernest Henry Wil- early years of the Arnold Arboretum, he was 15

also identifying most of the accessions, the described by the donating correspondent, majority of which were of known wild or-as in the case of garden forms-the culti- provenance. Sargent was a practicing tax- var had originated and been selected and onomist, deeply involved with the woody named by the contributing nursery. Lemoine plants of North America, and the leading den- hybrid lilacs and mock oranges come immedi- drologist of his era. Many others sought his ately to mind as examples. Although many of advice in matters of identity and nomencla- these are only of historic interest today, the ture, and he was extremely careful that the original plants or their asexually produced collection for which he was responsible would propagants are still growing in the Arboretum be correctly named and labeled. Moreover, he collections; they serve as living reference had described many of the taxa involved, and points for the garden forms popular during the some of the individuals growing in the decades surrounding the turn of this century. Arboretum collections were the very plants The identities of the Asian species that from which type specimens had been literally poured into the Arnold Arboretum as gathered. the result of expeditions by Sargent, John Jack, Of the accessions received from European and E. H. Wilson were largely determined by botanical gardens and nurseries, many com- Arboretum botanists who worked in the prised so-called "authentic" materials, mean- library and located in the Museum ing that the species involved had been Building. , German born and a

The taxonomic staff of the Arnold Arboretum pauses for a photo opportumty. From left to right Alfred Rehder; Ernest H. Wilson; Charles S. Sargent; Charles E. Faxon, herbarium curator and botamcal artist ; and Camillo Schneider, a German dendrologist who prepared treatments for Plantae Wilsonianae. Photograph ca. 1916, from the Archives of the Arnold Arboretum. 16

The Bentham and Hooker Planting Sequence in the Arnold Arboretum When confronted with the problem of how producing flowers with united parts. The the various accessions of woody plants magnolia family, the Magnoliaceae, was were to be positioned in relation to one considered one of the least derived groups another in the Arnold Arboretum, Charles of plants. Consequently, the magnolias and Sargent and Frederick Law Olmsted chose the closely related tulip trees were estab- to superimpose the natural classification lished near the Museum Building (now the system of Bentham and Hooker on the Hunnewell Visitors’ Center), where the Arboretum landscape as a guide for the planting sequence begins. Progressing planting plan. In essence, Sargent and through the collection from the Arborway Olmsted intended to indicate the natural Gate, one finds plant families of increasing relationships between the various genera morphological complexity (complexity and families of plants represented in the that sometimes includes reduction, conna- Arboretum’s collection by placing related tion, or loss of floral parts). The conifers, groups in close juxtaposition, thereby which Bentham and Hooker placed increasing the educational value of the col- together in a distinct group between the lection and allowing for easy access and dicots and monocots, came last in the botanical comparison. The system they Arboretum’s planting plan and were located chose to follow was one widely accepted by along Bussey Brook at the end of the origi- British and American botanists toward the nal road and pathway system. Inasmuch as end of the nineteenth century, which had there are few woody monocots, Sargent and been proposed by George Bentham Olmsted could end their planting sequence (1800-1884) and Sir with the conifers, and as if by a stroke of (1817-1911) in their monumental three- luck, the grove of native hemlocks on Hem- volume publication, Genera Plantarum. lock Hill fell into place in the planting Bentham and Hooker were leading English scheme. systematists during the nineteenth century Except for constraints placed on this plan and conducted their botanical investiga- by the ecological requirements of certain tions at the Royal Botanic Gardens at , groups of plants, each cohort or family was where Sir Joseph had succeeded his father, allotted space in the Arboretum in a more Sir , as director. or less linear sequence. Exceptions The Genera Plantarum, published in Latin included the placement of the willows adja- between the years 1862 and 1883, cent to the low-lying ground of the accounted for all of the genera of seed meadow, and the inclusion of ericaceous plants then known to science and included shrubs and flowering dogwoods in many precise descriptions of each. These genera locations because of their aesthetic appeal were grouped together based on their over- and their ability to knit the collection all similarities into "cohorts" (a grouping together into a harmonious whole. equivalent to today’s plant family), and the Over the years the Bentham and Hooker cohorts were similarly grouped into orders, planting scheme has not always been classes, and three major subdivisions: strictly followed. Beginning in the early dicots, gymnosperms, and monocots. 1980’s, however, restoration of the collec- Following the Bentham and Hooker sys- tions following the original plan has tem, plants producing flowers with separate proceeded, so that today the major group- or free floral parts were thought to be less ings in the collection adhere to the historic advanced, or more primitive, than those Bentham and Hooker classification. 17

A view of the pinetum, or conifer collection, above the banks of Bussey Brook. Photograph, taken in 1892, from the ArchIves of the Arnold Arboretum. self-taught taxonomist, arrived at the Arbore- tral and western China, arrived at the Arbore- tum in 1898 and was first employed to weed tum, Rehder’s interest in Asian plants was the shrub collection. Sargent, however, immediately aroused. He eagerly turned his quickly recognized Rehder’s keen taxonomic attention to those rich and ample collections. judgment and facility with languages. Moving Plantae Wilsonianae, a three-volume pub- Rehder indoors, Sargent gave him the enor- lication edited by C. S. Sargent, resulted from mous task of assembling the bibliographic the herbarium and library studies involved in data required for the Bradley Bibliography, a naming Wilson’s plants. Although Sargent five-volume, 3895-page publication that served as editor, Rehder did the bulk of the brought together references to all of the liter- work required in preparing the taxonomic ature on woody plants published up to 1900. treatments of the genera represented by Wil- At the same time he was involved with the son’s collections. In many instances Plantae Arboretum’s monumental bibliographic Wilsonianae gave synopses of all the Asian project-an undertaking that required a representatives of a particular genus. Wilson prolonged sojourn across Europe to visit himself contributed to the monumental libraries-Rehder was preparing the articles effort, as did specialists in Europe. Thus the on the important woody genera for Liberty foremost authorities of the day identified Wil- Hyde Bailey’s Cyclopedia of American Hor- son’s Chinese plants now growing in the ticulture. This work required intimate taxo- Arboretum and reviewed the pertinent nomic knowledge of genera ranging from nomenclature to determine their correct Abelia to Zenobia and Zizyphus. When E. H. names. In many instances they established Wilson’s shipments of dried, pressed speci- new taxa based on Wilson’s collections, and mens, which simultaneously documented his living plants grown from Wilson’s seeds were seed collections and the ligneous flora of cen- represented in the Arboretum’s living collec- 18

tions. The botanical descriptions published treatments in the book. This task, undertaken for these plants relate both to Wilson’s speci- by Rehder and Clarence Kobuski, constituted mens filed in the herbarium and to the grow- an earlier, comprehensive effort similar in pur- ing accessions in the living collections. By pose to the current National Science 1920 the collection of living plants that Sar- Foundation-funded project reported upon in gent was responsible for bringing together on this issue of Arnoldia. the Arboretum’s Jamaica Plain site was truly After his retirement from the Arboretum in a comprehensive living museum of the ligne- 1940, which occurred four days before his ous flora of the North Temperate Zone. seventy-seventh birthday, Rehder continued to With Sargent’s death in 1927 and Wilson’s work in the library and herbarium and once tragic, premature death in 1930, the influx of again turned to bibliographic work. The result plant materials intended for the living collec- of his final labors, which were based on his tions and generated by Arboretum-sponsored all-inclusive card file of literature references collecting trips slackened, but the ongoing for woody north-temperate plants, was his curation of the living collections continued. Bibliography of Cultivated Trees and Shrubs. Rehder had begun a card catalogue listing pub- Published in 1949, a little more than a month lished references to north-temperate woody before his death, Rehder’s Bibliography plants as he worked on the Bradley Bibliog- provided references for the accepted names raphy. This index, which is referred to by and listed synonyms of each species and Arboretum staff as the "Rehder Cards," was infraspecific taxon treated in his Manual. Also maintained throughout Rehder’s lifetime, included were the names and synonyms of with the result that changes in taxonomic species new to cultivation-plants like interpretation and nomenclature were con- Metasequoia glyptostroboides-that had been stantly monitored. Those changes that per- tained to plants in the living collections were noted by Rehder and Clarence Kobuski (Rehder’s assistant in the herbarium) and given to the appropriate staff, who made the necessary changes in the living-collections records and on the labels on the grounds. Another outgrowth of Rehder’s ongoing involvement with the taxonomic aspects of woody north-temperate plants was his Manual of Trees and Shrubs Hardyin North America Exclusive of the Subtropical and Warmer Temperate Regions, the first edition of which was published in 1927. This treatise, based to a great extent on the Arboretum’s liv- ing collections, quickly became the bible of horticulturists and nurserymen in the United States and abroad. Because of the great num- ber of Chinese species described and included in its keys, the Manual also became the guide to woody-plant identification most frequently Back issues of The Garden, a now-defunct weekly consulted by botanists in China! A second edi- British publication. Developing and maintaining an extensive library and archives for sta f f and visitor use tion of the Manual appeared in 1940, and a are part of the mission of the Arnold Arboretum. The concerted effort was then made to ensure that library, herbarium, and living collections together names in the identities and of the plants the compnse the interlocking institutional collections. Arboretum’s living collections agreed with the Photograph courtesy of Racz and Debreczy. 19

The Arnold Arboretum’s goal is to cultivate all those woody plant species and their infraspecific taxa hardy enough to withstand the climate of the Boston Basin [Massachusetts]. Three individuals of each species are to be grown, and an attempt is made to include individuals originating from different points within the geographic range of the species to ensure genetic and phenetic diversity. Plants of documented wild origin are highly preferred to those of nursery or garden origin. Although the collections of the Arnold Arboretum are not complete by these standards, work continues towards the acquisition and maintenance of a collection that is as comprehensive as possible. (Compiled from the Collections Policy published in Arnoldia, Volume 39, Number 6, pages 370-376, 1979.)

introduced after the appearance of the tematic studies by both Arboretum tax- Manual. onomists and specialists from around the The enormous body of Alfred Rehder’s bib- world. Additionally, the plants on the Arbore- liographic and taxonomic work (he was the tum grounds were available for easy compari- author of more than 1000 scientific publica- son using fresh materials, providing the tions), coupled with Sargent’s earlier work on opportunity to test the validity of taxonomic North American and Japanese trees and Wil- conclusions. They also allowed-as they do son’s contributions to the of vari- today-the study of characters not preserved ous groups like the Japanese cherries and the in dried specimens. To observe aspects of Asiatic , was reflected in the growth habit, bark characteristics, and chro- meticulous curation and verification of the mosome number (to name but three), it is best Arboretum’s living collections. All three men, to study living plants. as well as succeeding generations of Arbore- tum taxonomists, utilized in their work the Building on Established Traditions three major resources of the Arboretum-the After Rehder’s death the taxonomic review of library and its associated archives and photo- the living collections continued, but the graphic collections, the herbarium, and the emphasis in acquisition shifted toward hor- living collections-to the benefit of the ticultural varieties or cultivars that the nurs- Arboretum as a whole. Specimens in the her- ery trade was making available in increasing barium provided a basis for comparison with numbers. Donald Wyman, the Arboretum’s previously verified materials, many of which first horticulturist, played a pivotal role in had been examined and annotated by the placing the nomenclature of cultivars on a world’s leading authorities. The extensive firm footing and established in the Arboretum library provided ready access to original many cultivar reference collections for hor- descriptions and the results of additional sys- ticulturally important genera. In this work he 20

gave priority to obtaining authentic material Plain until it is planted in a permanent from the originators to ensure correct identity. location. Since the names of cultivars are not as tightly Several former staff members have been tied to documenting specimens and published instrumental in living-collections develop- descriptions as are those of entities given ment and the curatorial aspects associated botanical rank, errors are more frequent and with taxonomic and nomenclatural review. determinations, often subjective, are more Carroll E. Wood has contributed greatly to the difficult to verify. With these considerations curation of the plants of eastern North in mind, the Arboretum decided in 1979 to America, a labor of love that has been an out- embrace an accessions policy that placed growth of his efforts toward a Generic Flora restrictions on the acquisition of cultivars and of the Southeastern United States. Peter Green to reassert a collection policy that emphasized conducted in-depth studies of numerous botanical taxa. genera of Oleaceae and Ulmaceae, while Until the current National Science Richard A. Howard, Donald Wyman, Paul Foundation-funded verification project began, Sorensen, Burdette Wagenknecht, T. R. Dud- Arboretum taxonomists continued to make ley, Robert Hebb, and Gordon DeWolf made annotations to the cards in the living- extensive annotations in the records as they collections file in an unstructured fashion discovered errors in identification or changes when undertaking revisionary, monographic, in nomenclature during their tenures at the and floristic studies. Clarence Kobuski, who Arboretum. succeeded Rehder as herbarium curator, con- Current Arboretum staff continue to moni- tinued to survey new materials intended for tor nomenclatural changes and taxonomic the living collections to determine if they revisions and to annotate the living- were accurately identified. A new system with collections records accordingly. They have regard to nursery materials was inaugurated also played a major role in helping to develop after the Arboretum acquired the Case Estates the computerized format for the collections property in Weston, Massachusetts. It became data and to inaugurate the N.S.F.-funded verifi- customary for the horticulturists to move cation project. It is highly appropriate that the plants to nursery rows in Weston after they nomenclature and taxonomic identity of this had achieved an appropriate size in Jamaica historically and scientifically significant col- Plain. Once in Weston, the plants were lection be reviewed as the living-collections allowed to grow until they had flowered and records are computerized; the data contained fruited, at which time their identity could be therein will be available in a multitude of new checked for accuracy. Only after this precau- formats for all those interested in the woody tionary step had been taken were the trees or plants of the North Temperate Zone. Charles shrubs in question placed on a planting list Sargent, Ernest Wilson, and Alfred Rehder for establishment in their permanent location would be pleased. in Jamaica Plain. In more recent years this practice has been followed to a lesser extent, because of the ease of grow- primarily greater Stephen A. Spongberg is a research taxonomist at the ing materials in containers. As a result, most Arnold Arboretum and editor of the Journal of the Arnold Arboretum nursery stock remains in Jamaica Arboretum.