Polyxena identification and Daubenya comments

Robin Attrill Robin@rpattrill.freeserve.co.uk
Fri, 01 Nov 2002 10:56:44 PST
Mary Sue, Jim et al,
 
For a recent key to Polyxena see the excellent illustrated article by Terry Smale in the bulletin of the Alpine Garden Society, Vol 70, June 2002 pp 160-165.  The article is specifically about P longituba but all species are covered and most illustrated.

With Polyxena it is important to bear in mind that several taxa show considerable intraspecific variation, and, also, cultivation conditions have a pronounced effect on the appearance of the plants, with the foliage very susceptible to etiolation. In addition the foliage of seedlings is frequently rather different to that of mature plants.

It is to be hoped that the results of Alison van der Merwe's studies on the various genera of the Massonieae are available to a wide audience in the near future. In addition to the publication of P longituba, cited by Mary Sue, she has published preliminary data in an IBSA bulletin (vol 47, pp11-13). The previous conventional taxonomic coverage of the genus dates from 1976 (Jessop, J South African Botany, vol 42, 401-437) and is rather outdated.

Regarding Daubenya aurea, I would not be too concerned about failure to produce foliage at the start of the growing season, whether acclimatised or not, as in my experience plants frequently 'miss years' by remaining dormant. My oldest plant has only actually appeared during 5 growing seasons in the past 8!  The plant is likely to be relatively easy to acclimatise - certainly easier than irids.  I have always been rather surprised that such a striking plant, apparently widely available in commerce in S Africa (I believe ex Hadeco) has not been extensively commercialised elsewhere - an opportunity perhaps for an enlightened nursery to follow up?  Any person buying non-acclimatised bulbs in the N hemisphere should ensure that they were not illeagally collected from the wild where the plant is rare. 

Daubenya aurea is straightforward to propagate from seed but, as is so often the case, the label on the packet is no guarantee of correct identification!!!  In the Massonieae in general there is much incorrectly named material around. Fortunately most of the taxa are worth growing so it should generally not be too disappointing if the plants turn out to be something other than expected!

regards

Robin Attrill



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