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Registration of Plant Names

Plant name registration offers many benefits to those who are interested in plants, from commercial establishments to the general gardening public.  These benefits include collection and dissemination of flower and shrub data that may serve as an aid for identification purposes, information about parentage and source, and the avoidance of duplicate names for different cultivars.  Registration of plant names does not imply judgment of plant quality.

The Royal Horticultural Society (RHS) serves as the International Cultivar Registration Authority for genus Rhododendron.  The initial register was published in 1958; from 1962 through 1986, additions to the Register were published in The Rhododendron and Camellia Yearbook and Rhododendron with Magnolias and Camellias.  Since 1987, annual supplements have been published separately in booklet form.  References to RHS registration data are listed as "RHS xx" where "xx" refers to the year of publication.

Several of the International Registration Authorities are assisted by regional representatives around the world.  The American Rhododendron Society (ARS) serves as the North American representative to the RHS for genus Rhododendron.  Data collected by the ARS representative are processed, sent to the RHS for approval, and when approved, published quarterly in the Journal of the ARS (formerly known as the Quarterly Bulletin of the ARS).  References to these publications are listed as "ARS xxy" where "xx" refers to the year of publication, and "y" refers to the Number (1, 2, 3, or 4) of the appropriate year.

Physical data published by the two societies are identical.  ARS descriptions, however, may include the lowest temperature to which the plant has been exposed up to the time of name registration.  RHS descriptions usually omit any mention of hardiness ratings.

American Rhododendron Society
Executive Director: P.O. Box 525,  Niagara Falls, NY 14304
Ph: 416-424-1942   Fax: 905-262-1999   E-Mail:
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