International Rhododendron Conference, New York, 13-19 May 1978
From the Report to the Council
By Christopher D. Brickell, Director R. H. S. Garden, Wisley England
The above Conference held at the New York Botanic Garden from May 13-19 1978 was attended by some 70 delegates from the majority of countries where rhododendrons are cultivated.
The programme was designed to provide information on current scientific work being carried out on the genus. Topics included a review of past and present systems of classification of the genus; the value of indumentum, seed and cotyledon characters in taxonomy; genetic work within the genus; chemical analysis and its relevance in rhododendron taxonomy; and a review of cultivar nomenclature and International registration.
The taxonomic revision of the genus being carried out at the Edinburgh B.G. was outlined by Dr. Cullen and Dr. Chamberlain. Their work is nearing completion and publication will be carried out in stages over the next 2-3 years. They pointed out that the currently used system of dividing the genus into Series and Subseries had been originally intended by Bayley Balfour and other taxonomists to be a temporary method of dealing rapidly with the vast influx of new rhododendron material early this century; and that from a botanical standpoint some of the names currently used for the Series and Subseries had not been validated. Unfortunately a number of familiar Series and Subseries names would disappear in their revision as under botanical rules earlier published, valid names would have to be used but wherever possible familiar names would be retained.
A number of horticulturally important entities now regarded as species or botanical varieties would be "sunk" but it was clear from the discussion that Dr. Cullen and others at Edinburgh were very concerned about the horticultural problems which might arise when the revision was published.
Previous to the Conference, details of the Edinburgh proposals by Dr. Cullen had been studied and it was felt that from the botanical viewpoint they provided a very sound basis for the future classifications of the genus. Inevitably the revision will mean the loss of some familiar horticulturally recognized names if accepted and under the present Botanical Code there is no method of retaining these names.
One section of a lecture given to the conference (by the Director) outlined a possible method of maintaining for horticultural purposes familiar specific and varietal names. This involved redefining Article 26 of the Horticultural Code to allow formal recognition of the term "Group" to be applied to taxa of rhododendrons "sunk" in the Edinburgh revision.
As an instance var. roylei (of R. cinnabarinum) which would be sunk entirely under the Edinburgh revision would be maintained as R. cinnabarinum Roylei Group for horticultural purposes. This method does not involve any alteration to familiar names, merely an alteration in presentation and orthography, and means that horticulturally important entities can be maintained in recognizable form without offending the rules of the Botanical Code or creating a divergence of usage of names by horticulturists and botanists. The names would also still be available for use by horticulturists with only minor amendments to show schedules and nursery catalogues required.
The proposed method is more fully explained in the paper to be published later this year but was acceptable to both botanists and horticulturists attending the Conference. It was suggested that as the various parts of the Edinburgh revision were published a comparative table of equivalent Group names could be produced at the same time so that the relationship between the two could be established immediately.
From the Society's viewpoint it is recommended that the Rhododendron Handbook should be published using the present system of Series and Subseries but that cross-references should be included to the Edinburgh revision. This would provide a "system of equivalents" indicating that the Society was fully informed about proposed changes but was reserving its opinion until the Edinburgh revision has been fully studied. The subsequent revision and publication of a further edition of the Handbook will not be undertaken for some years, by which time the full implications of the Edinburgh revision should be clear and the Society's policy will be reviewed.