Haworthia as a problem genus (1970)


M.B Bayer, National Botanic Gardens of South Africa, Karoo Garden, Worcester.

Although many enthusiasts have recognized the need for a better understanding of haworthias as they grow in the field, South Africa has been very slow in providing the necessary interest.  Mr. G.G. Smith did a vast amount of work only to withdraw from the field before this work could reach fruition.  As a result, even his contribution has done very little towards solving the fundamental difficulties in the group.   Practically all the errors which can contribute to unsatisfactory classification have been made.  Perhaps the most unfortunate, and the most forgiveable, has been the total failure to recognize the importance of locality and variability.  In other words haworthias have never been studied on a population basis.  This has led to unnatural sections in which only superficial morphological characters have been used, and too many superfluous species and varieties which have no basis as far as the distribution of the plants is concerned.   Floral structure has several times been suggested as a possible solution to the problem of identification, but has never led to any further conclusion.  Why, of course, is very obvious.  To try and establish order from false foundations will never succeed.  The basic premise that the species described are true representatives of morphologically and geographically distinct species has never been questioned for the haworthias.  New species and varieties were freely described by Smith, von Poellnitz and Uitewaal (and Resendé) although the real identities of Haworth’, Salm Dyck’ and Baker’s species were in many cases unknown.

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