Guest column: Avonia papyracea

                   A contribution by Theo Heijnsdijk

Taxonomy
Avonia used to be a subgenus of Anacampseros, a relatively small genus in the family of purslanes (Portulacaceae).
The species within the genus Anacampseros consist of small to very small shrublets with a more or less thick, sometimes branched stem. The fleshy leaves form a flat rosette or are attached to the stem in a spiral. A typical characteristic are the stipules (lateral outgrowths at the base of the leafstalks). Often these have been reduced to hairs, or they have grown into parchment-like white scales which in some species can completely cover the stem including the real leaves.  In 1994 Gordon Rowley concluded that these species with scale-shaped stipules deserve the status of a separate genus and thus the genus Avonia came into existence. In it he placed 9 species. There are now 12.  The name is probably derived from the Latin ‘Avus’ which means grandfather. It would then refer to the white scales that give the plants an ‘old’ appearance. Rowley placed a few other Anacampseros-like plants in the genus Grahamia. For the genus Anacampseros itself, according to his classification, 15 species remain.
Together, the genera Anacampseros, Avonia and Grahamia form the branch (tribe) Anacampseroteae within the Portulacaceae.
Incidentally, it is doubtful whether the genus Avonia will hold. It is rather unusual in this day and age to base a genus on a similarity in its external appearance. As a rule, characteristics of the flower and seed and even more so the similarities and differences in DNA play the decisive role.

Flower and fruit
What all representatives of the Anacampseroteae have in common is the construction of flower and fruit.  The flowers, which in all species are only open for a few hours in the late afternoon, always have only 2 sepals, which first completely enclose the flower and often curl up after flowering  but remain joined at the tip so that they stay on top of the developing fruit like a cap. This can be seen very well in Avonia quinaria ssp. alstonii (fig.1).  At a certain moment the cap falls off and the seeds are released.


Fig. 1

Furthermore, there are usually 5 (sometimes 4) petals , which are white, pink or carmine. The stamens are white with yellow anthers and very variable in number: from 5 in, for example, Anacampseros comptonii to as much as 80 in A. quinaria (fig. 2).  The white pistil has 3 lobes.  The fruit consists of a kind of veined basket that often has a narrow opening at the top, so that the seeds come out in dribs and drabs as if with a salt-sprinkler as the flower stem bends to the ground and is moved up and down by the wind.

Fig 2.  Avonia quinaria ssp. alstonii has the largest number of stamens of all Anacampseroteae (up to 80).

A. papyracea was chosen as the type species of the genus because of its most pronounced characteristics. The name papyracea (=paper-like) is particularly appropriate because a stem really looks like a little wad of wafer-thin pieces of paper.  The name was given by the German botanist and director of the botanical garden in Königsberg, Ernst Heinrich Friedrich Meyer (1791-1858). The description in accordance with the taxonomic rules followed a bit later and is by the Austrian botanist Eduard Fenzl. It appeared in 1840 in a large article about the Molluginaceae (which at that time still included the Portulacaceae) in ‘Annalen des Wiener Museums der Naturgeschichte’. Hence the designation ‘E. Meyer ex Fenzl as found in botanical literature.

The white scales undoubtedly protect the green leaves underneath them against the bright sunlight. Rowley observed that under humid conditions the scales deflect somewhat from the stem so that there can be a better exchange of gases (oxygen, water vapor) with the environment. Perhaps water can also be absorbed in liquid form.

Like most Avonias, A. papyracea hails from South Africa (Western and Northern Cape). It is fairly common and grows mainly in plains with white quartz stones. But the plant also grows on dark coloured soil, where it is of course much more obvious. Figure 3, a photograph by Coby Keizer, shows a cluster in Goegap Nature Reserve east of Springbok.


Fig. 3

The former director of the Royal Botanic Gardens at Kew, Sir William T. Thiselton–Dyer, pointed out that the white stems bear a certain resemblance to bird droppings. It is not for nothing that the plant is also called ‘gansmis’ (goose dung) in South Africa.  Probably the geese have a different menu there than in Europe, because here the droppings of geese are just as green as the grass they eat.  Thiselton–Dyer suggested that this is a mimicry plant, which in this way tries to prevent it from being seen as a tasty snack.  If that is the case, then it does not seem to be a successful imitation, because another name for the plant is ‘haasieskos’ (Hare food). The same name is also used for A. ustulata and A. filamentosa.  Thiselton-Dyer made his remark in 1906 in an article in the British ‘Annals of Botany’.  At that time, the flower was still completely unknown.  In the same article he mentions that his friend Nicholas Edward Brown, also from Kew, had been growing the plant for many months, but despite daily observation had never seen a flower on it. Yet, suddenly a fruit appeared from between the parchment-like leaves.  He concluded that the flower had to be very small and hidden under the scales had fertilized itself.  A cleistogamous species, in other words.  Later authors also maintain that the flowers do not open. But that’s not true. Sometimes the plant does bloom and the flowers are not small nor do they remain hidden under the scales (Fig. 4).

Fig. 4.  The flower of A. papyracea and a seed pod.

Thiselton-Dyer also reported in the article mentioned above  that the stalk of the ripening fruit continues to grow so that the seeds are scattered at some distance from the mother plant.  This can also be clearly seen in Fig. 4. However, this is not always the case. In Fig. 5 it  can be seen that the 2 fruits hardly appear from between the scales.

Fig. 5. A full seed pod of A. papyracea and an already emptied one. Both only just visible between the scales.

In addition to the usual species which is nowadays referred to as A. papyracea ssp. papyracea, there is also a subspecies: A. papyracea ssp. namaensis. This occurs in the northwestern part of South Africa and in the south of Namibia and is distinguished by the fact that the scales are not smooth-edged but serrated (saw-edged) or toothed and by the seeds that are lumpy. In ssp. papyracea they are more prickly (Fig. 6).

Fig. 6. The seeds of A. papyracea are slightly prickly.

Seed collection is extremely simple. Holding an empty tube or something similar under a ripe fruit and a tap against the fruit are enough.  Immediate sowing gives excellent results. At a temperature of 25 to 30 °C, the seedlings emerge en masse after a week. Only a short time later, the seedlings proceed to develop the papery scales (Fig. 7).

Fig. 7

Fig. 8.  After a year, they are miniature versions of the mature plants.

Cultivation
I grow the plants in standard cactus soil and I also treat them like cacti. This means that they receive water regularly in summer and that I keep them dry in winter.  I try to keep the temperature in my greenhouse around 8 °C in winter, but it sometimes drops to just above freezing point.  According to the literature, even temperatures of 5 degrees below zero are survived.

Apparently, A .papyracea, like A. ustulata, was also used in South Africa as a kind of yeast for baking bread and making beer.  To this end, roots and stems are dried and ground. It is suspected that the plant also contains psychoactive substances, just as, by the way, A.  quinaria. The brew must have been a kind of ‘spacebeer’.

Literature

Browne, P. (1756). The Civil and Natural History of Jamaica. In Three Parts [3]: 234
Fenzl, E. (1840). Monographie der Mollugeneen, Annalen des Wiener Museums der Naturgeschichte, [2]: 295
Marloth, R (1917). Dictionary of The Common Names of Plants, The Specialty Press of South Africa, Ltd. Cape Town
Rowley, G. (1994). Anacampseros and allied genera- A reassessment, Bradleya 12: 105-112
Sims, J. (1811) Anacampseros filamentosa, Curtis’s Botanical Magazine 33: plate 1367
Thiselton-Dyer, W.T.(1906). Morphological Notes, Annals of Botany 20 (2) blz 123-127

Originally published in Succulenta 93: 2014. Translated from Dutch by FN.

 

 

 

 

 

 

 

 

 

Cheiridopsis pillansii

This species is a common sight on soft saline soil and low outcrops in the Richtersveld, from north of Lekkersing to the Augrabiesberg, at an altitude of 200-300 m. This is a winter rainfall area, which receives less than 100 mm rain per year.

It develops large, dense clumps 6-10 cm tall and up to 50 cm in diameter.
The more or less erect leaves are pale greyish white to bluish green, broad and thick (1-2.5 cm) and up to 4.5 cm long.
The flowers are 5-6 cm in diameter and range from cream and yellow to orange-red, sometimes with a purplish tinge. They appear in winter and spring (August-September).

 

 

 

 

CRASSULA COLUMNARIS

Guest column by Theo Heijnsdijk

C. columnaris was described as early as 1778 by the Swedish physician and botanist Carl Peter Thunberg. He has been called ‘the father of South African botany’ and ‘the Japanese Linnaeus’. From 1772 to March 1775 he was in South Africa and it is certain that in September 1772 he collected plants in the Little Karoo, one of the areas where this species occurs. From 1775 to 1778 he was a medical doctor in Deshima, the Dutch settlement in Japan. On his way to Amsterdam, he spent another 2 weeks in South Africa in 1778. It is plausible that Thunberg collected the plant himself or at least saw it in its natural habitat and therefore it surprises me that he gave it the name columnaris (= columnar).
In nature, C. columnaris is almost spherical, flat rather than elongated. It has been noted several times in literature that the species better could have been named C. globosa (= spherical). Perhaps Thunberg continued to cultivate the plants that he took with him for a while, resulting in them losing their natural appearance. This is a problem that these types of plants tend to suffer from in cultivation.

English-speaking people often use the name ‘khaki button’ which, in addition to the shape that the plant assumes in the dry season, also refers to the distinctive color that the plants adopt (see fig. 1).

The Afrikaans name ‘koesnaatjie’ for this plant also refers to the flattened convex appearance. A naatjie, also called naartjie, nartjie or nartje is a small citrus fruit that is halfway between a mandarin and a tangerine. Koes means in hiding, withdrawn. A mandarin in hiding more or less, probably referring to the way in which the plant partially withdraws into the ground in the dry season (I assume that the plant does not taste like a mandarin, even if it is edible). On the internet I found the following description of the koesnaatjie:
“A koesnaatjie is a succulent plant found in the dry western and southwestern regions of the Cape. The plant has thick, fleshy, oval-shaped leaves which are fused at the base and fold tightly over each other like roof-tiles, so that the plant has a compact appearance, and it is edible. Only once does it develop an inflorescence with densely congregated cream to yellow flowers after which the plant sets seed, withers and dies”.
In the 20’s and 30’s of last century, the Dutch monthly magazine ‘Succulenta’ regularly wrote extensively about this plant and the differences between nature and cultivation were always pointed out in detail. For example, in the November 1935 issue I read:
Miss W. v. A. in B. writes: “Can I take cuttings of an etiolated Crassula columnaris? They are so ugly with that brown piece of stem. What causes these plants to grow so spindly here?”
And the editors’ answer:
“The proper cultivation of highly succulent Crassula species in our climate is not easy. Many of these plants originate from the Karroo highlands. The average rainfall there is 4.47 inch ( ± 114 mm). In our country, an average of 700-800 mm rainwater falls per year. The rain on the Karroo plain falls mainly in the four winter months, sometimes also in November and December. These two months of summer rain have little influence on growth, but are important for replenishing the water reservoirs of the succulents.
Few deserts have a more desolate appearance in the dry period than the Karroo. There are no green plants to be found, the gullies are dry and the isolated “Koppies” (small mountain peaks) which are scattered here and there in the Central Karroo, seem to reflect the heat like a mirror. During the night a cool S.E. breeze prevails. The imaginary line which divides the districts into regions with summer or winter rains, runs through the Central Karroo near Beaufort West. In some winter nights the temperature drops below freezing point, and the mountain peaks are sometimes covered with snow, which, however, rarely falls on the plateau itself. The average daily temperature difference is large, i.e. 30° F (= 17 °C). Due to the intensely dry air, the summer heat is not very oppressive. In the Northern Karroo the average rainfall per year is even less, in the Western part 2 inches, so 51 mm per year. The average summer temperature in the shade is 110° F (= 43 °C). This gives us an idea of the conditions under which the highly succulent Crassulas grow in their homeland and makes us understand that it is therefore not easy for these plants to maintain their beautiful, stocky appearance here. Crassula columnaris occurs near Whitehill, the first train stop past Matjesfontein. Jacobsen mentions Namaqualand as habitat. The annual rainfall there is about 6 inches = ± 150 mm. Crassula columnaris allows you to take cuttings (the best time for this is August because the plant starts to grow in this month. After rooting, be very, very economical with water. The entire structure of the plant indicates moisture absorption from the air. In summer provide as much sun and fresh air as possible; the plants may turn reddish brown.”

It is remarkable that between 1923 and 1942, 5 times was written extensively about C columnaris in ‘Succulenta’ and after that, which is now over 70 years, nothing at all. The name is only mentioned in passing once in a while.
As can be seen from the above, C. columnaris belongs to the group of winter growers, which have their resting period in summer and should receive minimal water then. In many books a winter temperature of at least 15 °C is recommended, but in my experience that is not good at all. Such a high temperature combined with the application of water promotes growth and with the short days and the low light intensity in winter, this means an elongated, unnatural shape. I have never noticed that the temperature in my greenhouse – which I try to keep at least 8 °C in the winter (with varying success) – would harm the well-being or flowering of such plants.

Other members of the group of winter growers are C. alstonii, barbata, deceptor and pyramidalis. They are best grown in sandy soil with a small proportion of humus.
C. columnaris is monocarp, which means that the plant dies after flowering. This prompted Gordon Rowley in his book ‘Crassula’ to describe cultivating C. columnaris as “a passing pleasure”. Beautiful plants of the species are rare in our collections. Seedlings become elongated and imported plants immediately bloom and then die. To keep the plants somewhat presentable, Rowley recommends a starvation diet with plenty of sun and fresh air.
Although the first signs of flowering also announce the impending death of the plant, it is still fascinating to see how the inflorescence develops. It starts with the closed rosette bursting open at the top, as it were, to provide room for a compact arrangement of flower buds. See Fig. 2.


Fig. 2 The flower buds burst out of the plant, as it were

This is a plant I bought as a young seedling with the name “C. columnaris Lemoenshoek” at the Special Plant Market in Nijmegen. Lemoenshoek is a farm about 40 km east of the village of Barrydale in the Little Karoo. The photo was taken on December 3, 2012. The diameter of the plant in the photo is 4 cm and its height about 3 cm. In those 3 cm, 7 pairs of leaves are pressed together. Once in full bloom, the plant body is completely hidden from view by the numerous white flowers. See the photo of Fig. 3, which was taken on January 19, 2013. The name ‘shaving brush crassula’ used in English-speaking countries needs no further explanation.

Currently, 2 subspecies of C. columnaris are distinguished: in addition to C. columnaris ssp. columnaris (the standard form that this article is mainly about) there is also C. columnaris ssp. prolifera. The description by H.C. Friedrich dates from 1974. This subspecies branches off at the base and the inflorescence is not right above the rosette as with the other subspecies. When ssp. prolifera is going to bloom, the central axis lengthens so that the plant approximately doubles in height. At the top of the central axis, which is loosely covered with small leaves, the inflorescence develops, which is also less compact than in the other subspecies (see Fig. 4 below, photo taken on the Knersvlakte in August 2004 by Sofia Etzold), with thanks to ‘Photo Guide to Plants of Southern Africa).

In Afrikaans, this variety is called ‘sentkannetjie’. ‘Sent’ in this expression is derived from the English ‘scent’ and kannetjie stands for bottle. This does justice to both the shape of the plant and the sweet smell of the flowers.

Hybrids of C. columnaris are uncommon, but H. R. Toelken in the Flora of Southern Africa mentions a putative natural hybrid C. alpestris ssp. massonii x C. columnaris ssp. columnaris and gives the following information:
“The plants superficially resemble C. columnaris subsp. columnaris with its clasping leaves producing an erect column c. 15 mm in diameter. However, the plants are longer than broad and have terminal and axillary inflorescences and the leaves are bluntly acute as in C. alpestris ssp. massonii. The putative parents have been recorded from the area”.
Finally: C. columnaris should not be confused with C. columella, which has many similarities with C. columnaris in both name and appearance. This plant forms thin, branching, square columns of up to 1.5 cm thick and 5 cm high (columella means ‘small column’), consisting of tightly packed (tile-like) leaves. See below.


Fig. 5 Crassula columella also flowers terminally but does not die afterwards. Next to the faded head (right), one or two new shoots arise.

It also flowers terminally, with small, inconspicuously colored flowers on a stalk. Unlike C. columnaris, the stem does not die after flowering but forms 1 or more side shoots directly next to the flower stem, so that a low bushy plant is developed. For us, plant fanciers, this has the great advantage that the plant not only becomes more beautiful after flowering, but also provides a lot of easily rooting cuttings. This species is also hardly prone to the etiolation that C. columnaris so easily suffers from.

Literature:
Laren, van, A,J. (1931). Succulents, Verkade’s factories N.V., Zaandam.
Rowley, C. (2003): Crassula, Cactus & Co.
Swüste, F (1935). Vragenrubriek, Succulenta 17 (11) p. 175.
Thunberg C.P. (1778). Nova acta physico-medica Academiae Caesareae Leopoldino-Carolinae Naturae Curiosorum.
Photo Guide to Plants of Southern Africa, www.southernafricanplants.net

First published in Succulenta 92:5, October 2013. Translated from the Dutch by FN.
For more habitat pictures and other info follow this link:  Crassula columnaris (part 1 of 3)

 

 

Crassula deceptor

(Guest column by Theo Heijnsdijk)

Many Crassulas are beautiful mimicry plants. This one owes its name deceptor (= impostor) to the fact that the gray-green rosettes set with small dots look like small angular stones and in their habitat in southern Namibia and Namaqualand are hidden amongst the quartz stones that occur there.
The species was found in 1897 by Alston (of Avonia alstonii fame) and described by Schönland & Baker in 1902. Schönland later changed the name to Crassula deceptrix. This suggests that he considered cheating to be a trait that suits women more than men. But the real reason was that the word Crassula is feminine, and he thought (wrongly) that the species name had to be feminine as well. Later (1974) the name change was revoked.

Crassula deceptor is variable in shape and size. In nature the rosettes are about 2.5 cm in diameter and up to about 8 cm tall. The plant in figure 1 has the same width.


Fig. 1: Crassula deceptor resembles a jagged piece of stone 

The stems divide dichotomously and form a compact cluster over time.                                                                                                               For me in the Netherlands, the plant always blooms around October. As is the case with many Crassulas, this is not a spectacular but nevertheless graceful sight. The plants form branched flowering stems which protrude well above them and produce several tiny cream-green flowers which turn brown after flowering (fig. 2).  

Fig. 2: Crassula deceptor in bloom

As for its cultivation: full sun, little water in summer and none in winter. With a less sunny location and/or a lot of water, they do not retain the compact shape. Be careful with water staying behind on the rosettes.

C. cornuta (figure 3), also described by Schönland, is nowadays considered to be synonymous with C. deceptor. Yet it clearly deviates from the standard form of the species. The leaves are longer, more pointed and much lighter in colour.


Fig. 3: C. cornuta 

For the sake of completeness, it is worth mentioning that there are also quite a few hybrids in which C. deceptor is one of the parents. I have a hybrid of C. deceptor x C. susannae (fig. 4); the diameter of this plant is just 2 cm. 


Fig. 4: C. deceptor x C. susannae 

In ‘Crassula’ by Gordon Rowley, this cross is called ‘Dorothy’. He also mentions the following  hybrids: ‘Frosty’ (C. deceptor x tecta); ‘Gandalf’ (C.deceptor x mesembryanthemopsis); ‘Moonglow’ (C. deceptor x perfoliata var. falcata); ‘Shogun’ (C. deceptor x hemisphaerica) and the multihybrid ‘Star Child’ (C. deceptor x ‘Starbust’), ‘Starbust’ being a hybrid of C. ausensis x pyramidalis.


Fig. 5: Leaves of C. ‘Frosty’ 


Fig.6: Flowers of C. ‘Frosty’


Fig. 7: C. deceptor in habitat

Literature:
B.K. Boom (1980), De Crassula’s van onze collecties, Succulenta 59 [8]: 176-179

Mia C. Karsten (1941), Zuid-Afrikaansche succulente reisherinneringen I, de botanische tuin te Stellenbosch (6), Succulenta 23 [6]: 65

Gordon Rowley (2003), Crassula, Cactus & Co

First published in Succulenta 89 [2]: febr. 2010. Translation FN.

For more habitat pictures and info, see
A jewel in the Crassula crown: C. deceptor

Frithia pulchra (Guest column by Theo Heijnsdijk)

The first record
In January 1906, Ms. Olive Nation found a peculiar little plant. It was growing “on the top of the Magaliesberg, 5500 ft.”, near Rustenburg (South Africa). Today, that area belongs to the Northwest province, but at that time it was part of the now-defunct Transvaal province. She sent the plant to Kew Botanic Gardens near London for identification. Unfortunately, it did not survive the trip, but from the remnants, Kew botanist N.E. Brown deducted that it had to be a new species. Ms. Nation died not long afterward and attempts to get more specimens came to nothing.

“It bears a flower so it must be a plant”
Until in 1924 Mr. and Mrs. Dobie, who lived in the same area, on a Sunday hike in the mountains, suddenly saw reddish-purple flowers that seemed to grow directly from crevices in the rocks. Upon further examination, the flowers were found to be attached to small plants, consisting of 6 to12 short rods that were almost completely covered by the flowers. “Here’s something for your collection. It bears a flower so it must be a plant, Mr. Dobie is believed to have told his wife.

The first description
Mrs. Dobie sent a specimen to Frank Frith (1872 – 1954) in Johannesburg, a botanist who worked for the South African railways. Frith also came looking for it himself and he submitted some of the collected plants for the ‘South African Rockery’ of the Wembley Exhibition of 1924 (a kind of World Exhibition).
On December 10, 1924, Frith wrote to Mrs. Dobie:

That professor was the famous Nicholas Edward Brown, who worked in Kew from1873 until his death in 1934. In the 1920’s he separated many genera from the ever-expanding genus Mesembryanthemum. In the identification key he published in the journal ‘Gardeners’ Chronicle’ in November 1925, the generic name Frithia first appears. The description of the only species in that genus, F. pulchra, followed in 1926. He named the genus Frithia, to honor Frank Frith. In view of the above, it would have made more sense to call it Dobiea. The species name pulchra, by the way, is derived from the Latin pulcher = beautiful.
The original material collected and supplied by Frith is still present in Kew’s herbarium (fig. 1).

Fig. 1. Kew’s herbarium sheet with the original material collected by Frith in 1924.

Brown added an exclamation mark after his remark that the flowers of this plant lasted for up to three weeks.

The first published image
The oldest image known to me appeared in 1927 as record 275 in the seventh part of the magazine ‘The Flowering Plants of South Africa’ (fig. 2).

Fig. 2. Plate 275 of ‘The flowering plants of South Africa’ from 1927.

This magazine, published annually since1921 and edited by I.B. Pole-Evans, is reminiscent of the well-known ‘Curtis’s Botanical Magazine’: always a botanical drawing with many details on a full page, followed by a text of 1 to 2 pages. In this way, 40 plants were depicted and discussed each year. F. pulchra’s drawing was created by botanical artist Beatrice Orchard Carter; the text accompanying the image is by Louisa Bolus.

 Rapid integration
Amazingly, the species – of which only one locality was recorded at the time – quickly became widely known. As early as 1927, a slide of a F. pulchra in bloom was displayed at a meeting of the ‘s Gravenhage (Netherlands) branch of the succulent plant lovers’ association Succulenta. In 1928, Mr. E.J. Labarre (member of Succulenta since its inception in 1919) wrote an article in the weekly magazine ‘Onze Tuinen’ about Frithia. He had received plants from Mrs. Dobie himself and donated a seed tray full of them to the Botanic Garden of Amsterdam. In the same year, an article by the same writer appeared in the monthly magazine ‘Succulenta’, titled “The Frithia blooms!” with a picture of another seed pan, this time with flowering plants. With this exhibit, Mr. Labarre won a certificate of merit at the show of the Amsterdam Hortus. He added: ‘The finder, Mrs. Dobie, has always called them ‘Fairy Elephants’ Feet’. Isn’t that a suitable name for those who are romantically inclined?”
The name Fairy Elephants’ Feet is still used. In South Africa the plant is also referred to as  ‘Bobbejaanvingers’  (a bobbejaan is a baboon),  ‘glasies’  (glasses), ‘toontjies’  (toes) and  ‘Baby Toes’. Also called ‘Purple Baby Toes’ to distinguish it from the Fenestraria’s, which look like it and are also called ‘Baby Toes’ but have white or yellow flowers.

 Occurrence in nature
The plant also became a popular species in South Africa itself. This is evident from a comprehensive report in ‘Succulenta’ (8 pages) of a trip by Mr. F.W. Reitz of Pretoria in1935 from his hometown to the Rustenburg Gorge. Below are some of the passages from his report:

Being a passionate succulent collector, I already consider myself owning an extensive collection of succulents and also some rare cacti. However, the heavy rains of last November have ruined all my Frithia pulchra, so I planned to search for some of those beautiful plants.

A little further, diagonally opposite Rustenburg Gorge, lives Mrs. Dobie, the discoverer of Frithia pulchra. I know her well and had promised her I would come and see her collection of rare succulents.

That fine rose flower on the crystal-white quartz grit was the purpose of our trip, Carefully I wiped away the gravel, and only then did the characteristic rods emerge, with their transparent windows that absorb the sunlight, since the plant itself does not expose itself in order to protect itself from the drought. With long spikes, which Mrs. Dobie had supplied, we managed to remove the plants from the crevices: it had to be done very carefully because they were well secured, and the Frithias are very delicate. When I removed the gravel over a greater surface, it turned out that the ground was literally dotted with Frithia pulchra, and that without realizing it, we had walked over them. But it is remarkable that only on those flats covered with fine gravel and in solid rocks this special succulent could be found. Dry, intensely dry, it has to be there. And the power of the sun at 4500 feet (1372 m) above sea level, where the average winter temperature is 58° F. (14 °C), the average summer temperature is 72° F (22  °C)., and the average annual rainfall is only 25 inches  (635 mm), must be very strong.

The removal of these petite plants was not easy, but in the course of half an hour, we had more than 100 of them together. Carefully they were packed in a bag, and, glad to have achieved our goal, we made our way back.

Before packing the car and setting out on the return journey, I filled two flour bags with pure white quartz gravel. This came in handy, because I now keep my Frithia pulchra in a box, in which I have tried to imitate the natural conditions at the site on the mountain as faithfully as possible. Yet I have failed to keep the whole treasure alive. Within a week, about 50% of my Frithias suddenly dried up. The rest, on the other hand, is safe and sound. I am very satisfied with the result. Frithia pulchra possesses the same property as many other aristocratic plants, i.e. that they are very difficult to replant and very peculiar about unaccustomed living conditions: too much water, too rich soil and too little gravel can be the cause of Frithia pulchra’s death.

So much for Mr. Reitz’s account. This story clearly shows that you can easily overlook the plants.
In figure 3 we see what looks like a piece of land with some grassy plant growth. But in reality, it’s full of F. pulchra. Within the red circle, there are three clusters.


Fig. 3. Locality somewhere southeast of Rustenburg. In the indicated area there are 3 clusters of Frithia pulchra. Photo Werner du Toit

Figure 4 shows the same site with a corresponding circle.
Fig. 4. Many specimens of Frithia pulchra among quartz gravel and in crevices, with the same area encircled as in fig. 3. Photo Werner du Toit

These photos by Werner du Toit were taken on January 28, 2017, in the middle of the growing period. In the dry season (winter), the plant tissue contracts due to dehydration and so the plant bodies are even pulled completely into the ground. The quartz gravel in which the plants grow can become very hot in summer. In harsh winters it may freeze there. In summer it can rain heavily and the plants clearly enjoy that.  Flowering in South Africa also takes place in summer (December through February).

Fig. 5. Frithia pulchra in bloom in habitat at the end of January. Photo Werner du Toit

Nature conservation
Fortunately, in these times people no longer work as described above by Mr. Reitz. On the IUCN Red List of Threatened Species, F. pulchra has the status of ‘vulnerable’. The distribution area is limited to a number of localities in the Magaliesberg region and is estimated to be less than 5 km2. The biggest threat is illegal collection, but it is assumed that this has not had a major impact on the occurrence of the species. The populations are stable. The fact that the plant is easy to grow and that plants collected in the wild usually die may play a role in this.   The area of the Magaliesberg is now a protected nature reserve, the Magaliesberg Protected Environment (MPE). It runs roughly from Rustenburg to Pretoria.

The genus Frithia
As mentioned above, the genus Frithia was established in1925. Today it is one of more than 120 genera in the Ruschioideae, one of the five subfamilies of the large family of Aizoaceae  (the ice plant family). The grouping into genera is based, among other things, on the construction of the seed capsules and therefore not easy to understand for the average enthusiast. The genus Frithia however is easy to tell apart from the genus Fenestraria – which at first glance bears a lot of resemblance to Frithia – by the way the leaves are arranged. In Frithia, the leaf position is spiral, whereas in Fenestraria the leaves are placed crosswise. Also, in Fenestraria the leaf surface is smooth, whereas in Frithia it is divided into tiny lens-like structures (fig. 6 and fig. 7).

Fig. 6. In Frithia, the leaf surface is covered with lens-like structures. Photo Theo Heijnsdijk
Fig. 7. Six-week-old seedlings of Frithia pulchra. The first ‘rod’ with lens-like structure develops between the cotyledons. Photo Theo Heijnsdijk

In his 1925 description of both genera, Brown commented that the leaf surfaces do not contain chlorophyll. He indicated that you can easily ascertain this by cutting off the top of a leaf and looking at it against the light. This works, but it’s also quite destructive.

 A second species
Brown knew one species: F. pulchra. In 1968 H.W. de Boer described in ’Succulenta’ some different plants that he had received from a C.G. Booker in Transvaal. The deviations concerned the much smaller leaves and flowers, the colour of the leaves (“rose-like greenish-brown”), and the colour of the flowers (white with the tips of the petals tinted rose-violet). The locality could not be established because Mr. Booker had since died. De Boer described this form as F. pulchra var. minor (= smaller). Because no material was deposited in a herbarium, the description is invalid. In the year 2000 Patricia Burgoyne et al. described the plant as a new species: Frithia humilis. According to the dictionaries, humilis means low or near the ground, but according to Burgoyne it is ‘smaller than others of its kind’. One of the photos accompanying the 1968 article by de Boer is now the lectotype of F. humilis.
Bronkhorstspruit, about 50 km east of Pretoria, is indicated as locality (fig. 8 and 9).

Fig. 8. Frithia humilis north of Bronkhorstspruit .  Photo Sean Gildenhuys


Fig. 9. Frithia humilis north of or Bronkhorstspruit in bloom. Photo Sean Gildenhuys

It is worth noting that Louisa Bolus in ‘The Flowering Plants of South Africa’ mentions that the South African lawyer and plant collector Douglas Gilfinnan had already found F. pulchra at the place Witbank at the end of December 1905, just a few weeks before Mrs. Nation. That is about 200 km east of Rustenburg and about 40 km east of Bronkhorstspruit. This may also be F. humilis.

Cultivation
In cultivation, we grow Frithia pulchra with its leaves above the ground. The risk of rot is high if we don’t. The soil should be granular and well permeable with a small proportion of organic matter. Keep absolutely dry in winter. The plants will certainly start to shrivel then. In spring, light misting is recommended. Once the plants are filled out, you need to water them regularly. The plants should not start to shrivel during this time. Flowering time occurs with me in the Netherlands in June-July. It is wise to limit the amount of water afterward, because the growing period is rather short.

Fig. 10. Frithia pulchra flowering in cultivation. Photo Theo Heijnsdijk

Propagation by sowing works fine, but is also possible by cuttings. This is done by carefully dividing a rosette in half and planting the pieces after the wounds have dried. But don’t do this if it’s your only plant, as there’s a good chance of rot occurring.

Literature
Boer, H.W. de (1968). Frithia pulchra var. minor 47: 147.
Bolus, L. (1927) Frithia pulchra, The flowering plants of South Africa 7: text accompanying  plate  275.
Brown, N.E. (1925). Mesembryanthemum and some new genera separated from it. The Gardeners’ chronicle  78: 433.
Brown, N.E. (1926). Ficoidaceae in J Burtt Davy, Manual of the Flowering Plants and Ferns of the Transvaal 1: 41, 162.
Burgoyne, P.M. & Smith, G.F. & Plessis, F. du. (2000).  Notes on the genus Frithia (Mesembryanthemaceae) and the description of a new species, E humilis, in South Africa, Bothalia 30 (1): 1 – 7.
Labarre, E.J. (1928). De Frithia pulchra, of romantiek in de  botanie, Onze tuinen 23 (6): 61.
Labarre, E.J. (1928). De Frithia bloeit!, Succulenta 10 (12): 215 – 219.
Reitz, F.W. (1935). Frithia pulchra, Succulenta 17 (6): 81 and 17 (7): 97.

First published in Succulenta 99 (2), 2020. Translated from the Dutch by F.N.

 

 

 

 

Othonna cacalioides (incl. O. minima, O. pygmaea)

Othonna cacalioides is a dwarf compact caudiciform with a flattened potato-like caudex, most of which is below ground. The plant body is broader than tall and to 10 cm across, covered by a tough leathery bark of a muted brownish or orangish colour.
The branches are reduced to low lumps with thickish, 2-2.5 cm long, and 0.8-1 cm wide leaves (only present in winter and spring).
From May to October, the plants produce inflorescences with 2-8 cm long stalks, each with up to six small, yellow flower heads.

Usually, the plants are found in shallow rock pans with a thin layer of coarse sand in sandstone pavements in the Northern and Western Cape (Bokkeveld Mountains to Gifberg). Sometimes they occur in patches of greyish moss. In both cases, they are often and hard to find, especially when not in leaf.
Although they are slow-growing and difficult to keep alive, this seems to make them only more attractive to collectors.

P.S.
In 2012 the Swedish botanist Bertil Nordenstam created a new genus (Crassothonna) with 13 species, formerly part of Othonna. One of these species (O. carnosa), for nomenclatural reasons, had to be renamed Crassothonna cacalioides. This has unfortunately created quite a bit of confusion because many people assume (understandably but wrongly) that this is the new name for Othonna cacalioides.

In short:  Crassothonna cacalioides is what used to be called Othonna carnosa and Othonna cacalioides is still Othonna cacalioides.

Together with Braunsia maximiliani


 

 

 

 

Antimima (Ruschia) biformis

The conspicuously dotted leaves are typical of this species, which is one of the smallest in the genus.

Over time the plants form low cushions up to 2.5 cm tall and 18 cm in diameter.
The leaves are of two types:
one pair forms a body of 2-5 mm long with 2 very short lobes, greyish-green with a purple hue. During the hot and dry resting period, this pair dries out and forms a dry sheath-like cover which protects the consecutive pair.
In this second pair, the leaves are almost free, 2-7 mm long and 2-3 mm wide and thick, triangular in cross-section, and pointed.
This phenomenon of two different types of leaf-growth is called heterophylly and it may be interesting to note that it is reflected in the name of this species (bi=two; forma=form, shape).
The plants have solitary purplish flowers (with or without a darker mid-stripe) on stalks 3-4 mm long.

According to the literature, they occur in shaly sandstone crevices in the Swellendam area. The first picture below was made about 20 km NW. of Montagu, the others about 15 km E. of Montagu. The last two ones show plants in late January (during the resting period), the other ones were taken in early September (during the growing season).

Othonna intermedia

Of the about 100 species of Othonna, roughly a third qualify as succulents. Nine of these are deciduous geophytes (leafless during the resting period) and O. intermedia is a member of this group.

A resinous underground tuber produces a number of wedge-shaped, fleshy leaves up to 7 x 4 cm in size and green to blue-green or greyish in colour.
The yellow flower heads are 0.8-1 cm in diameter and appear between May and September (mostly in June and July).
Endemic to the Knersvlakte, where it occurs in quartz patches.

Mesembryanthemum liliputanum (Phyllobolus abbreviatus)

Usually, this dainty geophyte (up to 5 cm tall) only has a few leaves and flowers on slightly woody stems produced from tuberous roots.
The leaves are 4-ranked and almost cylindrical, they are covered in big and beautiful water-storing bladder cells. The pale yellow flowers are about 2 cm in diameter and appear in August-October.

Occurring on shale or loamy soil covered with quartz pebbles in the Vanrhynsdorp area.

Cheiridopsis peculiaris (eselore)

A peculiar species indeed and therefore easy to recognise.
The plants are up to 5 cm tall, usually with up to 3 branches. They form two types of leaf pairs: in the first one the leaves are flat and largely free. In the second pair they are upright and fused for more than half their length; this pair becomes dry and papery in summer, so that the new growth is protected from drying out.
The flowers very large (up to 6 cm in diameter) and appear in Aug.-Sept.

Found on shale flats and gneiss slopes in northern Namaqualand (from Springbok to north and west of Steinkopf), an area with 100-200 mm rainfall per year (in winter).