Haworthia Updates Vol. 7 – Table of Contents

Haworthia Updates vol. 7

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Volume 7, Chapter 7:- More on Haworthia mirabilis and H. mutica from east of Bredasdorp.

More on Haworthia mirabilis and H. mutica from east of Bredasdorp.

M B Bayer, PO Box 960, Kuilsriver 7579, RSA

The area concerned is the long and wide contact zone between the Limestone stretching from Bredasdorp to Potberg, and the Bokkeveld shale north of that.  The soils and vegetation of the two areas are grossly different.  The limestones are agriculturally almost useless, while the shales are prime wheat and pasturage producing soils although relatively low yielding.  The vegetation of the shales is Renosterveld and there are very few patches left.  Large areas resemble ecological deserts with nothing of the original surface intact.  Here and there are shale banks and associated quartz outcrops and also some remnants of tertiary deposits that overlie the shale.  Under this deposit layer the shale has decomposed to kaolin and in places there are gravel sheets of fine quartz on white clay.  The skeletal nature of these remnants is the saving grace but it is unbelievable to what lengths farmers must have gone to make fields arable.  Enormous amounts of stone that have been carted away and dumped to make cultivated lands.  Sadly the stone is often dumped on exposed rock and prime Haworthia habitat.  The remnants are still under threat and a mindset that has developed in the road construction and maintenance arena is that roads must be clean and scraped fence to fence.  Similarly there are farmers who want every square inch under control and in subservience to their production needs.  Dense vegetation is abhorred and burnt to control predation of sheep by jackal and lynx.  Vegetation adjoining crops is treated with weedkiller to minimize crop contamination.  Crops are also grown in conjunction with animal production.  When crops are in, the animals are on fallow land and on whatever is left of natural vegetation.   It is the harsh reality of conservation.

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Volume 7, Chapter 6:- Field trip to Van Reenens Crest and Niekerkshek.

M B Bayer, PO Box 960, Kuilsriver 7579, RSA.

The objective was to explore some likely habitats previously observed at Van Reenens Crest and nearby.   We extended the scope to include further exploration for Haworthia mutica as I am still questioning the place of this species in the greater scheme of things.  Thus here are four sets of populations that I report on viz. H. mirabilis, H. retusa ‘nigra’, H. floribunda and H. mutica.  See maps Figs 1 and 2 for geographical position.

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Volume 7, Chapter 5:- Still more Haworthia mutica and Haworthia mirabilis

It so happens.  Heidi Hartmann first visited the Karoo Garden more than 35 years ago and it has been very difficult for me to pay attention both to her mesems and all my other plant interests.  In the last few years she has been working on Acrodon .  This is a small genus of only 5 to 6 species that occurs in the Southern Cape with much the same distribution and habitat requirements as Haworthia.  She had had some second thoughts on a species she had described as Acrodon calcicola and intimated that she needed photographs to show what proves to be detaching fruits (capsules).  So off we went to get that northeast of Bredasdorp at Rooivlei.  But Nick Helme had about a year before sent me an intriguing picture of a greenish soft looking plant from near the DeHoop Reserve entrance road to the east.  I had considered that it might be an equivalent of the H. muticaXmirabilis population at Die Kop (MBB7500) that Ingo Breuer usefully described as H. hammeri .  I use the name with great trepidation because to say what is correct usage is difficult.  It could pass as a cultivar name, a varietal name or a form name.  I am quite sure it has its origins in the interaction of two species and that is what a botanical name should reflect that; thus H. muticaXmirabilis or however else the nomenclaturists may require.  So these journeys are never without distractions as Rooivlei itself is a remarkable site.  I find that I have few images of the populations of Haworthia that occur there.  The product is nearly all pictures/images.

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Volume 7, Chapter 4:- What is typical Haworthia mutica?

A supposed new species of Haworthia viz. H.groenewaldii Breuer, is described in an article authored in Alsterworthia 2.2:15-20 by Breuer, Marx and Groenewald.  It presents the description of this supposed new species from Buffeljags east of Swellendam that I would simply have identified as another variant of H. mutica.  This is not because I am confounded by the variability among the plants in the genus, or even in any one species.  I recognize the species as systems of populations in which the individuals vary from one another as one would expect in any group of living things that maintains the flexibility to adapt to constantly changing world conditions.  In this even time becomes a variable.  I think species are very important elements if the whole of creation and not just for taxonomist and collector activity.  Other people have other ideas of what species are, so my disagreement is hopefully forgivable..

Although H. mutica was described by Haworth in 1821 it was not allied to a South African field population until recognized by Col Scott in 1985.  G.G. Smith had failed to recognize it when he described his H. otzenii in 1945.   The type by which the name is supported is a Kew illustration reproduced here as Fig. 1.  This then is what one would expect a typical representative of the species to look alike.  Now the ever present problem in Haworthia, is that no two plants in a population may look quite the same.  Hence my problem with the description in which the word “typical” is rather bandied about.  It falls into the first aspect of taxonomy.

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Volume 7, Chapter 3:- A field trip to the Potberg area.

Introduction:

These field trips are always made with some objective in mind in respect of new exploration.  In this case I wanted to get more pictures of H. mutica as it is a species that I have few digital images of.  There were also localities that I remembered from the days when I was sweeping the countryside at a fairly coarse scale and was not much bothered by detail.  I confidently expected the number of real species conforming to that in other fields of botany and zoology, to be in the region of 33.  I never dreamed that such divergent views would, or even could, arise from less information than even then available to me.  So while 450 names were whittled down to the mid-hundreds by me, students of the genus have in recent years pushed that up to the 600 mark.  My opinions have been couched in quite conservative terms but it is a problem of the nomenclatural system that an identification in respect of a Latin name evokes a reality that does not exist.  I maintain that the problems we experience in Haworthia are no different to that which exists in many animal and plant genera.  I think that primarily this is because of the absence of insight into, and understanding of, the actual nature of species and the two dimensional model we use to relate them.  Species are very variable systems because they have to be to survive the constantly changing world they occupy.  In this article I am just going to present images of plants within populations of four different species viz. H. variegata, H. minima, H. mirabilis and H. mutica.

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Volume 7, Chapter 2:- Further exploration in Haworthia. Further to finale.

The writing of my grand finale was inspired by several things. One of these was another item of a mind-numbing foray into the classification of Haworthia. So I asked that deep thinker and observer, Gerhard Marx, for a devil’s advocate (abbrev. DA) point of view which he has done with the same competence he has as an artist. I have many times in my writing addressed the issue of a species definition and produced one too. Not surprisingly the first thing the DA does is dismiss my definition without producing one of his own. Simply being able to say that an indeterminate number of plants from some population are sufficiently different in respect of a character or two from other haworthias, is motivation enough for the generation of a new name?

The case of H. groenewaldii Breuer, described in an article authored in Alsterworthia 2.2:15-20 by Breuer, Marx and Groenewald is the case in point. It presents the description of this supposed new species from Buffeljags east of Swellendam. The article is written in the first person (Breuer) who quotes extensively from Gerhard’s e-mails, and includes a piece by Jannie Groenewald under the heading “Description of the Vegetation type and distribution”. The overall impression is of an article that conforms to the style of a forgotten era and it is not possible or sensible to attempt a rational dismissal.  Who is actually responsible for the article and how does one correct misleading statements without giving offence?

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Volume 7, Chapter 1:- Haworthia retusa ‘nigra’ – Another grand finale.

Introduction
I wonder.  I have written so many words purporting to be my last that my credibility here too must be under stress.  Two very recent articles of mine in Alsterworthia deal essentially with that issue, although they also cover the discovery of Haworthia mutica (Buffeljags) (= H. groenewaldii Breuer).  They do not cover my subsequent thoughts on actually reading the description of this new “species” by Breuer, Marx and Groenewald.  I hope that the present manuscript will explain why I reject this as a Latin binomial although anyone who is in the least familiar with my writing should already know.  Spurred on by that discovery, I instigated a search in another area of the Buffeljags valley adjoining the Bontebok Park accompanied by Jannie Groenewald who informed me of what he had found in still another area I had long wanted to explore.  So I instigated another search there too and again with Jannie.  A discussion of these new finds is submitted to Cactus and Succulent Journal where I trust it will be published.  The essence is already in Alsterworthia and this article is written to widen the readership, submit more pictures and maintain continuity with the 6 volumes of Haworthia Update that Harry Mays has been so conscientiously and determinedly publishing.  This is all writing that may not otherwise have seen the light of day.  I am personally extremely grateful for that as I have had a mania since writing my revision Haworthia Revisited and Update Vol. 1 (both Umdaus), to set the record straight and explore all the unknowns, or at least some of them.

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Haworthia Update Volume 7 – Essays on Haworthia by Bruce Bayer

Haworthia Update Volume 7 is now available from Alsterworthia International. For details contact editor Harry Mays at hmays@freenetname.co.uk or by writing to

Harry Mays
Woodsleigh, Moss Lane, St Michaels on Wyre, Preston
PR3 0TY, United Kingdom

Seven chapters in four parts:
Chapter 1 – Haworthia retusa ‘nigra’ – Another grand finale
Chapter 2 – Further exploration in Haworthia. Further to finale
Chapter 3 – A field trip to the Potberg area
Chapter 4 – What is typical Haworthia mutica?
Chapter 5 – Still more Haworthia mutica and Haworthia mirabilis
Chapter 6 – Field trip to Van Reenes Crest and Niekerkshek
Chapter 7 – More on Haworthia mirabilis and H. mutica from east of Bredasdorp, and
A rationalization of names in Haworthia, A list of species with new combinations and new synonyms by M.B. Bayer and J.C. Manning.

Bruce Bayer’s Haworthia Update Essays on Haworthia Volume 7 is A4 size, printed on A3 paper, folded and stapled. Part 1. has  63  A4 pages,  Part 2.  83,  Part 3. 57 and  Part 4. 48. The field work is profusely illustrated with plant  photographs, maps and a pie chart. Part 1 has over 330 photos, Part 2 over 280, Part 3 over 330 and Part 4. over 160. Recommended retail price is £45.50  + p & p. It may be ordered from good book sellers.

Haworthia Updates Vol. 7 – Table of Contents

Haworthia Updates vol. 7

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