2 NATL. ARBORETUM CONTRIB. NO. 3, U.S. DEPT. AGR. 



The majority of cultivars of /. opaca are selections brought into cultiva- 

 tion from the wild throughout the natural range of the species. Although 

 the naming of cultivars in /. opaca was initiated at the beginning of the 

 20th century, there is a disappointing lack of information on performance 

 trial data. Accordingly, recommendations for tested and superior clones 

 for particular geographic areas are rarely mentioned in this checklist. 



The checklist in its entirety will include names of all cultivated Ilex; 

 Part I, the present checklist, includes only those names pertaining to 

 /. opaca. 



Common names of cultivar names have been excluded to avoid nomen- 

 clatural confusion. 1 For each name cited, at whatever rank, the publica- 

 tion and validity, source or place of origin, discoverer or selector, namer, 

 introducer, registration, and patents of the plant have been determined. 

 Synonyms are cited only when used to designate plants known in cultiva- 

 tion. Original and amplifying descriptions are given, if available, and 

 all previously published information is documented. 



Some cultivar names of recent origin that have not been previously 

 published are published and validated here for the first time in Appen- 

 dix A. 



A general lack of understanding of horticultural nomenclature often 

 leads to great problems. Identical cultivar names have often been applied 

 to more than one clone. Named cultivars from commercial sources have 

 often been originally referred to ranks of botanical status; that is, of 

 form {forma) or variety (varietas). In trade and professional publica- 

 tions, improper use of nomenclature with reference to rank and categories 

 of cultivated plants has resulted in multiple duplication of errors. 



This checklist, adhering to the International Code of Nomenclature of 

 Cultivated Plants — 1969, will serve as an organized guide for updating 

 and correcting names of cultivated plants. This guide particularly applies 

 to the clarification of the rank of "cultivars," which are often known as 

 cultivated or horticultural forms or varieties. Every name is documented 

 as valid or invalid, or as a synonym. A published description, no matter 

 how short or inadequate, is an integral part of validation and is specifically 

 required for all cultivar names published on or after January 1, 1959. 



The policy adopted for accepting descriptions that validate cultivar 

 names is liberal. Very few descriptions of /. opaca cultivars clearly distin- 

 guish the hundreds of cultivars. Furthermore, morphological descriptions 

 that will distinguish all named clones of /. opaca probably could never be 

 constructed. Validation of cultivar names is based strictly on the Interna- 

 tional Code of Nomenclature of Cultivated Plants — 1969 and does not 

 judge the merits of any clone. The International Registration Authority 



1 Dudley, T. R., and Eisenbeiss, G. K. handbook of hollies. Amer. Hort. Mag. 

 49(4) -.315.1970. 



