I have several times been rather taken aback when botanists have been among those who have derided the fact that I have not apparently looked to flowers as a source of characters for identification of Haworthia species. Others have intimated that there are diagnostic characters in the seeds and even in the capsule structure. The essence of this kind of complaint is that there are these definable units called ‘species’ and that there is some linear and dichotomous set of characters by which they can be separated. The perception remains alive for the technology of surface structure, pollen sculpturing, DNA and molecular structure, and expectations which flow from and for these real and presumed character sources.
My opinion is that these techniques or methodologies will not tell us much more for Haworthia than what can be deduced by common-sense scrutiny of the plants. They may be extremely exciting and enlightening in view of broader relationships and theories of origin and migration even of vegetation. But their value to the collector and grower will always be minimal.
In a very interesting book by Stephen Gould entitled “Rock of Ages”, in which he propounds his principle of NOMA – non-overlapping magisteria. This states that science and religion should not be confused nor mixed.
So this is not a confession of confusion – you do not confess to what is obvious. It is an admission, and an admission can be construed as an apology. But, as a rhetorical question, how can one apologize and expect forgiveness when one continues to walk the errant path?
I started to write about Haworthia to dispel confusion, and yet more than 40 years on, this confusion has not become any less. The conclusion I have come to (and I wish it was a closure) is that the prime source of confusion is simply the human condition. In mystic philosophy one can read… “Born in ignorance, we live in ignorance and we die in ignorance”.
I think that my interest in Haworthia stems from my conscious effort to dispel this primal confusion and find some of the order in my view of creation. The classification of plants suggested just one small piece of my world which was available to me, and Haworthia as one group which no one else could explain to me. What have I now learned and what contribution does this make to dispel confusion?
My courage to now say something more directly arises from a recent request by SANBI to write a synopsis of Haworthia for an E. Cape Flora. I feel that I have done that fairly successfully. The problem is now to produce a similar product for the SW Cape and this is considerably more difficult.
I was contemplating the problem I see in the way we approach classification, contending that there is no resolution to the endless addition of new names and arguments about their validity and usefulness unless we reach some agreement on method and purpose. The confusion about names, descriptions and identifications that had arisen in 1947 came about for four reasons. Small samples and inadequate exploration, too many unqualified experts, lack of insight into what species actually may be, poor methodology.
There is no excuse for this situation to continue. Sampling is at a very high level and because the other three elements have not been removed, confusion is as great as before. Many names may have been lost from sight, but there is no lack of new ones to replace them. Experts are a problem and their qualifications even more so. In my own experience I have communicated with many highly qualified botanists who have contributed absolutely nothing to the resolution of problems as basic as typification of names, or definition of the word ‘species’. So what then contributes to qualification? This is surely an unbridgeable problem when amateurs have dabbled so freely in plant classification with apparent success. But their success has come from the failure of qualified botanists to put something more substantial in place than a nomenclatural code for binomials and nothing to indicate what those should mean, or who is competent to generate or change them.
Haworthia flowers – some comments as a character source.
M B Bayer, PO Box 960, Kuilsriver 7579, RSA
The object of this essay is to discuss where we are now with respect to classification of Haworthia. Despite my comments and observations stretching over 50 years, there are still taxonomists writing and arguing on the basis of method and practice that generated the anarchy of names that existed at the start of my involvement. This method is what is probably referred to as “typological” i.e. there is a single herbarium specimen and anything that departs from this in some mind catching way is a different and thus needs a new name. At the generic level, recent DNA studies show that Haworthia is indeed three separate entities (the subgenera), and that these cannot be rationally separated from the aloid genera. Formal classification requires that Haworthia thus be subsumed in Aloe (see Treutlein et al, Rhamdani et al and Daru et al). This is both incomprehensible and anathema to writers and collectors locked into method that does not rest on any insight to what the problem of species actually is, let alone take proper cognizance of the problems that exists at generic level.
2. THE RACEME. Figures Set 2 show the bases of the peduncles in several collections to again show how variable they are and not only because of plant vigor and current growth conditions. Diameter can vary by a factor of three. Color is variable and the bract spacing and size of bracts as variables must be noted. Fig 6 is simply a robust spike in a population where the flowers were sparsely spaced on the stem with approximately 15-20 flowers per stem, whereas this raceme had nearly 30 flowers. The number can drop to as low as three. In 7917 we noted a single plant with an inflorescence of over 600mm where the average was below 300. Similarly at 7818 there was one colossal inflorescence of 800mm where again the average was between 300 and 400mm. There is a real problem in that the typological attitude is often adopted when making comparisons like this. An extreme example would be to take H. retusa south of Riversdale as typical of the species. These are massive plants (source of ‘Jolly Green Giant’) and the inflorescences are huge with many flowers. This is not typical for the species and especially so if one takes the mountain cliff populations (H. turgida) to be the same species (as I do) where the plants are proliferous and the inflorescences many and reduced. Plants in poor niches and even poor habitats, flower weakly and the inflorescences are reduced. Figs 7 shows varying capsule positions on the stem. Figs 8 and 9 show a distichous and a secund inflorescence and figs 10 to 15 demonstrate the varied spacing of the flowers that is observable even in any one population although the images are for two different accessions. In Fig. 8 the middle flowers are in a single plane and I regret not having observed the leaf arrangement in that specific plant, because this is a distichous arrangement as the low Fibonacci number of a spiral arrangement of the flowers. This may have been reflected in the leaf arrangement too. The spacing and arrangement of the flowers is also a variable and the number of flowers may also vary. Figs 16 to 18 show bud arrangement and the way in which the fish-tail buds have upturned tips. Although the peduncle does continue to lengthen, most of the lengthening takes place in the flower producing area and towards the upper end of the raceme. The peduncle does not always stay straight and may bend slightly at each floret. The number and distance of the flowers along the peduncle may affect bud packing just as peduncle formation in the rosette results in the appearance of a groove on the leaf face. This is a secondary physical phenomenon and is not an inherent “character”. The leaf keel for example may also be influenced just by physical leaf-packing. A peduncle of a flower from the centre of a plant will have a many angled base, but one arising from a leaf axel only 2-angled. Generally the raceme is indeterminate, meaning that it does not end in a pedicel and flower. But I have seen an individual raceme of H. floribunda with a terminal flower. This exemplifies our problem where characters one might think could be used to determine even genera, are variables at species level.
6. THE CAPSULES. Figs 6.1 first size differences that can be found within individual inflorescences. The remaining images show 8 capsules per population for a few populations to show variation in size and shape. The way the capsule ripens and splits is very variable. In some cases the capsule is pinched near the end but the locule tips flare outwards. This has the effect of seeds being retained in the capsule. In others the locules flare regularly and symmetrically from the base and the seed is all easily released. In the Van Reenen Crest populations the capsules were inclined to be a reddish hue. But colour can vary depending on the ripening process and they also bleach with time. Fig.6.4 7978 shows this in capsules drying after the peduncle was taken, and retaining their greenish colour. In H. floribunda the capsules are smaller and it appears that they may flare at the tips more in splitting and be coarsely crispate. This is not always the case but it is a tendency in the smaller capsules to do this. Fig. 6.7 is of capsules in 7910 H. floribunda, Rietkuil; compared against 7913 H. mirabilis also Rietkuil east of Swellendam. It is quite evident that even a capsule structure as apparently characteristic as in H. floribunda, is replicated in a different species. Fig. 6.8 is of 7955 Van Reenens Crest, and 7262 south of Greyton. I thought the capsules of 7955 were smaller, reddish coloured and slightly rougher than those of 7262. But the capsule structure in the entire genus is very similar to those shown on this figure and it is just not conceivable that some feature will stand out and resolve issues that exist in respect of the entire group.
Some criticism about my supposedly having ignored the flowers in Haworthia comes at a very inopportune time. I set aside flowers for the reasons very obvious from the historical record but also because of the considerable problems of similarity in the appearance of the flowers in apparently quite different species. My priority was a geographic overview and a rational basis on which discussion and decision making could be based. It I just grossly unfortunate that other writers and critics seem to be wedded to a classification paradigm locked into the approach that prevailed 70 years and more ago. This in the total absence of a species definition other than the vague acceptance of a zoological one based on interbreeding capabilities. This ignoring the ease of hybridization among Haworthia variants in general.
While I have written an account of flower appearances in a small selection of populations, I also came across these few images I have of flowers in what I regard as the species H. nortieri. I have also added images of a single flower of H. maculata from a population high in the mountains at Worcester that could be seen as a southern extension of the H. nortieri set of populations. Note must be taken of my early contention that H. nortieri and H. globosiflora were the same species, based on my observation of the intermediate appearance of the flowers of a Vanrhyns Pass population. The H. maculata bud is typical of the species in the Southern Cape, whereas H. nortieri has rounded bud-tips.
The flower of the Trawal plant are dramatically different from that of, say, Sneeuberg. It is very understandable that differences like this lie at the base of all the argumentation and confusion that so despoils the naming and identification of Haworthia. A classification has been needed against which to explore and examine these differences. It seems to me totally unnecessary to try and construct another hierarchy of solely Latin names while so little is still unknown.
It has long been my contention that there is no separation between Haworthia retusa and Haworthia turgida. It is one very variable system viz H. retusa, with a larger fairly non-proliferous plants tending to level areas and then smaller proliferous plants on steeper habitats. There is huge variability among members of any one population and of course much more between populations. Over and above this is the relationship of this apparently one single system, with H. mirabilis that is probably even more complex and varied. If one takes all the known populations and variants into consideration it become necessary to ask if H. retusa and H. mirabilis are also not just elements of one system , and one species. If all the considerations are summed and referral is made to vegetation and speciation drivers; what constitutes an area of endemism, then I am sure the answer will be “Yes”! What seems to have happened is a natural sequence. As sampling has progressed so has there been recognition of differences. The logical outcome is that sampling progression should lead to understanding and synthesis by reduction. Unfortunately there will be diehards that stay with the differences syndrome and cannot see the similarities.
My writing has been described in all kinds of terms, hermetic and pretentious being two of the adjectives used. Recently Kris Tamayo also suggested that he had trouble understanding what I wrote or write. The fact is that writing and expressing yourself is difficult. But the first place is to be clear about what you want to say. Or is that in fact the first place?
Writing is a means of communication and it really only should start when you are clear about what you think and what you want to say. Then it requires that the listener is clear about what he/she wants to hear and has the common cultural heritage that permits communication and understanding to occur?
In writing and talking about plants I personally get very frustrated by the technical problems of definition and knowledge that mess up communication completely. This is one of the obstacles in classification where there is no species definition and we do not actually know what species are. There are a lot of other obstacles. Recently someone wrote and implied that there were a lot of significant differences among Haworthia that could be used to arrive at a better classification (than any already available). The point I would make is that this person has his own idiosyncratic view of what significance means. This is not strange at all because a prominent scientist was once applying the statistical measure of standard deviation to two and three measured samples. That measure probably cannot be used until many more measurements are made. What is taken to be significant may be quite irrelevant to the actual question of whether there are more or less species. This is why amateurs and collectors should keep clear of classification. The professionals already have too many problems.
The characters we use to make identifications are important in that they may be of the yes and no kind i.e. present or absent, or they may be graded from vague to prominent. So it is very easy to go to one end of the scale and take only the prominent or what happens to strike your eye. This is exactly what happens. Unless followers and interested parties realize the impact this sort of decision making affects what they may want to know and understand, there can never be any harmony and peace in the classification process.
Look at these flowers and see what you can glean from them…
These just happen to be the only three flowers I have of a few plants of Haworthia herbacea from recent sampling. They are shown here in correct proportion to one another with the third being 18mm across at widest spread of the two upper outer petals. So we have two things we can call characters i.e. size and colour that we could say in respect of this simple sample, that they are significantly different. No matter how many times or how we measured these two things, this fact would stay the same. The plants happen to be from two populations and we can then ask if this is true for those populations. I did ask such a question of both H. herbacea and H. reticulata, and ended up by learning that I needed a sample of about 200 flowers to arrive at a statistically true answer at a probability of 95%. The thing is that I could go a little further south and sample another population and get a really pink flower with a spread of 25mm or more that would nearly double the spread of my measurements.
There are several incidentals here. One is the delineation of the mouth into the tube of the flower. Why is it so clear in the third picture? The second is that the first flower has not opened as flat across the face as the other two despite being at the same expected state in respect of time from opening. The third is that the name “subregularis” was used in this genre of flowers because the petals are so equally spread; perhaps less-so in the middle picture. Still a fourth curiosity is that in the southwestern species with the more extreme biarcuate bud with the fish-tail tip, is how the tips of the upper outer petals are “replicate” – i.e. the margins tend to fold together. In the Worcester/Robertson Karoo particularly H. herbacea and H. reticulata have the “regular” flower shape. But in H. mirabilis in this area, the upper outer petals may be held in a plane directly behind the inner outer petal and do not spread at all. There the bud tip is still fish-tail and the upper outer petal tips very replicate.
This is an unusual population in that it is the most northwestern one known although only about 15km from Klipport nearer Stormsvlei. It is the source of the single plant that developed gross milkiness and for which I coined the name “Silver Widow”. The population was first recorded by a Mr Meiring who worked as a nurseryman for the Bonnievale Nursery of Hurling and Neil in the years at least prior to World War 2. There is a letter in the Compton Herbarium archive which records a transaction between Meiring and Triebner of 100 plants as 1s ea (i.e. = 10cents in today’s currency.). I really struggled to find plants again in a very disturbed area and eventually did so after I had placed “Silver Widow” there in her pot to see if the flowers would be pollinated in situ. Indeed they were and then found about 20 plants in a very small area nearby. This visit owes to the report by Jakub Jilemicky of still more plants a very short distance again from these. Here there are about 80 plants in an area of about so many square meters.
Illustrations of the plants and flowers are given. The only comment I can make is to repeat that I never ignored the flowers out of ignorance. The fact is that we have a number of pretentious experts who have no concept of species other than an inherited vague notion that species have something to do with the capacity to interbreed. The fact that Haworthia plants do so freely does not handicap their enthusiasm for new species either. So this is a bit of irony. My contention was that if you did consider flowers there would be a lot less species than even in my conservative approach. In fact I am quite sure a competent professional taxonomist might well consider that I have been too generous with species and too kind to my critics.
This flower (H. pumila) is apparently persistently regarded by botanists as actinomorphic (star-shaped, radially symmetrical) – as though zygomorphy (yoke shaped, bilateral, asymmetrical) in the aloids is an uncommon condition!
Radial symmetry means the flower can be divided into 3 or more identical sectors which are related to each other by rotation about the centre of the flower. Typically, each sector might contain one tepal or one petal and one sepal and so on. It may or may not be possible to divide the flower into symmetrical halves by the same number of longitudinal planes passing through the axis. Zygomorthic flowers can be divided by only a single plane into two mirror-image halves, much like a yoke or a person’s face.
If you see the way the inner upper petal overlaps BOTH the two lower inner petals, you recognise that there can not be actinomorphy in aloid flowers.
Kobus drew my attention to a glabrous plant of H. pumila while he was photographing this species at Lemoenpoort. The plants here have a missing chromosome and tend to have a purplish colour. I have seen smooth non-tubercled leaves elsewhere. But do check out that one plant – if you look carefully you can see the leaves are in 8 nearly vertical tiers. Proper botanists recently, for Taxon, described the arrangement of leaves like this in only two tiers (e.g. H. truncata) as “distichous insertion”. This is weird. Are the leaves in this plant of H. pumila “octichous”? Is H. viscosa “tristichous”. No. The leaves in the aloids are alternately and spirally inserted.
Two further records and data for Haworthia mirabilis.
Kobus Venter drew my attention to a second population of H. mirabilis on the eastern boundary of the farm Schuitsberg, which is the origin of the var. beukmannii of von Poellnitz. But the real motive for exploration in that area was a photograph sent to me by Messrs Daryl and Priscilla Hackland of a plant on the Zigzag Path just east of the northern end of the town of Greyton. It was their son Andy Hackland who observed the plants and thought I might be interested – indeed. The bright green colour of the plant struck me as most unusual for that area where most of the populations known are south of the river in shale and they are of the brown and red hues. This is not strictly true because records of an expedition by messrs Beukman, Otzen and others mentions a small “black” species just before the entrance to Greyton. I have never found that.
Three further records and data for Haworthia mirabilis.
The populations covered here are:-
6631 H. mirabilis ‘mundula’, Mierkraal, SW Bredasdorp.
6635 H. mirabilis ‘badia’, NW Napier.
6639 H. mirabilis ‘sublineata’, S Bredasdorp.
There has been some published comment about the distinctiveness of these three populations stating that I do not recognise this because I treat them as variants of single species. The implication is that I do not see any difference. This is quite bizarre. At the present moment I have a digital library of 165 H. mirabilis populations and this is by no means all there are. There is an enormous amount of variation both in and between these populations. If the specified three are to be recognised as species, it means that there is a wholly unrealistic number of species quite out of keeping even with an already highly diverse set of species of the Cape Flora. Furthermore,as I point out in appendix 6, there is no typical variety of H. mirabilis in any practical sense because the variability in the population designated by me, as well as that of Schuitsberg apparently preferred by another, precludes it.
Appendix 8 to Vol. 8 Haworthia Update. A report on Haworthia mirabilis ‘badia’ / ‘subtuberculata’
I cannot claim that I have resolved the nomenclature niceties around the use of this name and its many varietal names and synonyms. If critically examined even the use of the name “mirabilis” is in doubt and the very original epithet of “Aloe atrovirens” may be nomenclaturally correct. This would create havoc because then the name H. herbacea as typified by W.T. Stearn may best apply. So I put that all aside and use names as I have in my Revision and subsequent publications. I am well aware that there is a problem with the use of H. mirabilis var mirabilis where it may be thought that the name “mundula” is therefore redundant. I cover all this up with the explanation that there is no typical variety “mirabilis” and actually use just the name H. mirabilis to cover all those populations and variants to which no Latin names exist. I use names like “badia” and “sublineata” as it is generally possible to recognise all or most of the variants from those populations. But names like “magnifica”, “maraisii”, “heidelbergensis”, “rubrodentata”, “beukmannii” and “depauperata” (among others) have no clear and direct application in respect of a population or even a group of variants of any kind. In my Revision I attempt the use of the name “triebneriana” to cover all the variants that are not included under the typical varietal name “mirabilis”. This does not actually work either because the name has its origins at Stormsvlei and there are other populations that are very different from those occurring there too.
Appendix 9 to Vol. 8 Haworthia Update – A report on Haworthia mirabilis and Haworthia rossouwii ‘minor’, Rooivlei, NNE Bredasdorp.
In Appendix 8, I explain some of the rationale of my use of names. A detailed report on H. mirabilis can be found in Haworthia Update Vol.3. and in various chapters of the subsequent Updates. It is shown why I consider the possibility that H. mirabilis and H. retusa are in fact the same species.
In this report I will show just one population of many from Napier northwards and westwards for which no broad name exists. There is simply a transformation from elements that I refer to as H. mirabilis ‘subtuberculata’ in Appendix 8, to a very wide range of populations in the central Southern Cape. Both the names “maraisii”and “heidelbergensis” have been applied to populations in this area. The name H. maraisii var. simplicior from Napky may even be relevant but its application, simply irrational.
Appendix 10 to Vol. 8 Haworthia Update – An additional report on Haworthia mirabilis and Haworthia rossouwii ‘minor’, Rooivlei and Brakkloof, N and, NNE Bredasdorp.
The previous report indicated the necessity for further exploration of Rooivlei. I had observed H. mirabilis, but not reported it in Update 3, at Brakkloof to the west in 2004. So the object of this appendix is to remedy this oversight and to also cover more area of Rooivlei. At Brakkloof there are several small remnants of rocky shale and we located several populations, while at Rooivlei we actually explored the very western boundary. This constitutes the same topographical area as the Rooivlei populations but the plants we observed were factually on Brakkloof.
In appendix 6 I reported on H. mirabilis just east of Greyton and also at Schuitsberg further east and south. I undertook this excursion to fill out on a population at Uitkyk (MBB7092) west of Genadendal illustrated with one image in Haworthia Revisited. En route we discovered still another population along a road from Caledon to the northwest (8055 Hammanskraal), briefly called at a site east of the bridge on that road crossing the Riviersonderend (MBB8056). We also visited the population MBB8040 east of Greyton and explored some of the hiking trail between Greyton and McGregor.
The population 7092, H. mirabilis, at Uitkyk, is indeed interesting. It is a steep riverside, south facing, vertical slope. There are many plants that may not receive any direct sunshine for most of the summer and of course none in winter. It is really curious because there are groups of plants that seem to be holding clumps of moss, lichen and a modicum of soil to the rock. There are orchids, oxalis, shade-loving Asparagus, and all the small bulbs one expects in these moist south facing habitats. The rock seems to be metamorphosed from fault-shearing heat and pressure on shale. Among the illustrations is a view looking east along the road with the roadside south-facing habitat on the left. The Riviersonderend River is immediately on the right. In the distance ahead is Leeukop, the type locality for H. mirabilis ‘rubrodentata’. That is a dry north-facing slope.