Articles: BULB CHAT August 2002 PDF Print E-mail
Thursday, 26 May 2011 23:17

BULB CHAT AUGUST 2002 No. 30

NEW BABIANAS

There are a few new Babiana species that have as yet not officially been named. Most of them come from the area to the north and to the west of Vanrhynsdorp, to as far north as the Springbok area. This includes the magnificent one that appears on page 50 in " Namaqualand

A Succulent Desert " by Cowling and Pierce with magnificent photographs by Colin Paterson-

Jones. It also includes a new one that is currently flowering in IBSA cultivation, and by the time you read this it would have been back at the Compton Herbarium. It was collected by

Dr Peter Goldblatt and Dr John Manning, who asked us to grow it on for them for future studies.

KATBAKKIES PASS

In 1919 J.E.P. Levyns spent 6 weeks prospecting in the Swartruggens, probably the wildest and least known area of the Western Cape. He said the name Katbakkies meant Little Cat Faces. We have not previously come across this explanation, though we have heard several others. He tramped a distance of more than 150 miles. The farms Katbakkies, Groenfontein and Zuurvlakte, three enormous areas of bleak mountaintop, formed by a 50 mile long anticline of the hard quartzites of the Witteberg series of rocks when they had been folded upwards forming the Cedarberg to the north and the bastion of the Matroosberg to the south. Is there a chance of another discovery like that of Clivia mirabilis ?

FEEDING : TIPS FROM A SUCCESSFUL GROWER

Many of us have experimented for years with various feeding-regimes. One of our successful growers has noted that despite feeding his Lachenalias with Potasium Sulphate the leaves do not look too happy. The leaves seem to be brittle and break easily. He had previously fed his Lachenalias with 3:1:6 with great success. His plants were always extremely vigorous and they just looked good. This year he is not happy with the condition of the Lachenalias.

Feeding the Iridaceae with Potasium Sulphate at 5 ml to 5 liters of water seems to do the trick. The leaves are greener than usual and the plants are more robust. Those brown leaf tips are a thing of the past. It might be a good idea to alternate the feeding of Iridaceae between 3:1:6 and Potasium Sulphate. The Potasium Sulphate will also lead to bigger corms at the end of the growing season.

GARDEN GLADIOLI

In the gardens of the world there are thousands of Gladiolus cultivars and hybrids. They all started in the Cape though quite early on species from the Eastern Cape and then from Natal and then subsequently from the Transvaal and eventually from Rhodesia ( if you will excuse the names then in use ) took over. The first successful hybridist was Dean William Herbert who was breeding new forms between 1810 and 1847. None of his survived. The earliest grower whose hybrids still are grown was Colville, a nurseryman in Chelsea who produced Gladiolus colvillei in 1823. He described it as G. cardinalis x G. blandus (now G. carneus )

but it seems more likely that it was G. cardinalis x G. tristis, for it was strongly scented. In

1830 a G. ramosus was bred in Holland from G. cardinalis x G. floribundus - again more likely G. cardinalis x G. oppositiflorus. In 1837 Bedinghaus, gardener to the Duc d'Aremberg at Enghein in France, produced Gladiolus gandavensis which was very probably a cross between the red and yellow forms of Gladiolus psittacinus ( dalenii to you ), though possibly G. dalenii x G.oppositiflorus. From then on, although more indigenous species were pressed into use, many of the new hybrids were based on those first classical ones as one or both of the parents.

BULBINELLA

Many IBSA members grow Bulbinellas. The impression I get at the monthly meetings is that very few of us know anything about Bulbinellas. We tend to guess when it comes to identification, because very few of us have taken the time to study this interesting group of plants. Bulbinella is a small genus belonging to the family Asphodelaceae. Bulbinellas are found in the winter-rainfall region of the Western Cape in South Africa and also in New Zealand. After Pauline Perry's work " Bulbinella in South Africa", published in 1999, we now acknowledge 17 species of Bulbinella in South Africa and 6 species in New Zealand.

The genus Bulbinella was established by Kunth when he discarded the genus Anthericum L. and divided the taxa then known among the three genera Phalangium, Trachyandra and Bulbinella. The first Bulbinellas to be described were what we know today as B cauda-felis and

B. triquetra.

Bulbinellas had long been regarded as belonging to the large family Liliaceae. Recent work has brought along a new classification with Liliaceae split into smaller families. Bulbinellas now belong to the family Asphodelaceae and to the subfamily Asphodeloideae. This subfamily includes the genera Bulbinella, Bulbine, Kniphofia and Trachyandra. The other subfamily Alooideae includes Aloes, Gasterias, Haworthia and Astroloba. The difference between these two subfamilies is the fact that in subfamily Asphodeloideae the tepals of the flowers are free or connate at the base and the tepals are spreading or campanulate. In subfamily Alooideae the tepals are fused below into a tube and are erect or shortly spreading above. Not a major difference to write home about !! This was one of the reasons for the debate about including Aloes into the group of plants that IBSA grows, talks and writes about.

All Bulbinella species are deciduous geophytes ranging in height above ground from about O,2 to 1,2 m. The underground stem is a compact corm-like structure with an apical shoot surrounded by membranous or fibrous sheaths extended to form a neck. Numerous swollen roots arise basally and laterally from the stem. A new stem disc and swollen roots are formed annually towards the end of the growing season. Plants are dormant through the dry summer.

Leaves are produced annually and die down at the end of the growing season. The leaves are erect and linear and arise directly from the upper side of the reduced stem. Some Bulbinellas have narrow leaves while others have broad leaves. The leaves are normally without hair

( glabrous ), but very occasionally the leaves may be sparsely covered with fine, longish hairs.

The inflorescence of Bulbinellas is an unbranched, dense raceme. The flowers are stellate with the 6 tepals joined at the extreme base. Flower colour is most commonly yellow, but white as well as cream-coloured flowers and rarely orange flowers are also found.

When identifying Bulbinellas the first thing to do is to look at the size of the leaves. The first group has leaves of different sizes, with the largest leaves towards the outside and the smallest towards the inside. The plants are usually taller than O,5 m and the flowers could be yellow, orange, cream-coloured or white. This group includes the following species : B. elata,

B. nutans, B. latifolia, B. punctulata, B. potbergensis, B. barkerae, B. eburniflora, B. cauda-felis and B. graminifolia. In the second group the leaves are all equal to nearly equal and the plants are mostly shorter than O,5 m. The flowers in this group are either white or yellow. The species in group 2 are B. gracilis, B. nana, B. chartacea, B. divaginata, B. trinervis, B. ciliolata,

B. triquetra and B. elegans.

At the last IBSA monthly meeting there were 3 of the 4 subspecies belonging to Bulbinella latifolia on display. On show were the yellow B. latifolia ssp latifolia, the orange B. latifolia ssp doleritica as well as the rare B. latifolia ssp toximontana from the Gifberg with cream-coloured flowers. The absent one was B. latifolia ssp denticulata from the Worcester and Ceres areas.

REPRODUCING LACHENALIAS VEGETATIVELY

If Lachenalia leaves are cut or broken off and left to lie on moist shaded grit, they form a corky covering at the point of severance and bulbils form there and even some distance up the leaf. The grit moist and out of direct sunlight.

GARIES - AUGUST 2OO2

Four IBSA members were invited to visit a farm about 15 km to the east of Garies over the first weekend of August. We stayed at the Garies Hotel and spent nearly a complete day on this wonderful farm. On our arrival the first plant that we saw was not in flower, but in leaf. We saw hundreds or even thousands of Brunsvigia plants. This was the largest colony of Brunsvigia bosmaniae that any of us had ever seen. More plants than what we had ever seen at Glen Lyon at Nieuwoudtville. Can you imagine what it must look like towards the end of March when they flower in their hundreds. When we started walking we were soon confronted by fields of a Babiana with truncated leaves and blue flowers. At first we thought that it was Babiana truncata, but the shape of the tube troubled us. It was obviously a tube with a kink to it. That evening we could positively identify the plants as Babiana pubescens. There is a close superficial resemblance between Babiana truncata, B. pubescens and B. flabellifolia. All three these species have truncated leaves. The leaves of B. pubescens could be up to 2,5 cm wide, while the leaves of B. truncata are up to 1,4 cm wide. The tube of the flower of B. pubescens is curved with a distinct bend near the throat. The main colour of the flowers of all three these species is light blue to purple. B. pubescens has some red on the lower tepals which the other two don't have. Just to confuse us even more there is now a fourth species with truncated leaves - Babiana cuneata. From the little information we have about this species we know that the blunt ending leaves are not as wide as those of B. pubescens. B. cuneata has flowers not extremely dissimilar to those of B. flabellifolia. We spent quite some time flat on our stomach trying to photograph these Babianas. The idea was to get the tube in focus from the side, and also to make sure that the truncated leaves, and the red in the flowers, could be seen.

The next interesting pairing we saw was Lapeirousia silenoides and a few Lapeirousia dolomitica ssp lewisiana. Both these species have magenta flowers. The L. silenoides is spectacular in it's own right, but we were extremely pleased to see the L. dolomitica ssp lewisiana. According to the revision of Lapeirousia by Peter Goldblatt it is very seldom seen. The type collection of this Lapeirousia was made by Nordenstam near Komkans, about 100 km to the southwest of where we were.

We also saw some magnificent specimens of Lachenalia carnosa. Those that were growing in the shade were huge, with big glossy leaves. Not as abundant as the L. carnosa was another species of Lachenalia, L. mutabilis. This was the variety from the Garies/Springbok areas, with duller flowers than the L. mutabilis found at Clanwilliam. We also saw 2 species of Gethyllis,

Gethyllis britteniana growing in the open surrounded by L. carnosa as well as Lap. silenoides.

Gethyllis verticillata was found growing near the granite boulders, in shade for a large part of the day. We saw leaves of Haemanthus crispus everywhere.

Another interesting plant that we saw was Aloe krapholiana. This is a small Aloe with relatively large flowers and banded leaves. We saw a few plants, some with huge seedpods. On the rocksheets were various succulents including some beautiful yellow Cheiridopsis cigarettifera.

We ended our stay by slowly driving ( 4 x 4 ) along a tract to the highest point in the area , from where we could see for many kilometers. To the west we could see the sea, definitely more than 70 km away.

LAPEIROUSIA VIOLACEA VS LAPEIROUSIA JACQUINII

Every purple to violet coloured Lapeirousia that we see is not Lapeirousia jacquinii. We have all seen Lap. jacquinii at places like Nieuwoudtville and Vanrhynsdorp, but near Clanwilliam and in the Bidouw Valley we also find Lap. violacea. The flowers are very similar but Lap. violacea lacks the white markings on the margins of the lower segments of the tepals. Lap. violacea can also be recognised by the absence of crisping or serrations of the stem and bracts, and by the presence of long spiny cusps on the base of the corm. Just to confuse us the two species grow together in the Bidouw Valley as well as about 5 km south of Vanrhyns-

dorp on the road connecting the N7 with the road to the Gifberg.

ANGIOSPERMS

Often at monthly meetings the term Angiosperms is thrown about. The Angiosperms, or flowering plants, constitute the dominant vascular plant of modern floras of the earth. The term Angiosperm ( which literally means 'a vessel seed' ) was devised to designate one of the most definitive characteristics of flowering plants, namely the enclosure of the ovules or potential seeds within a hollow ovary. In this respect Angiosperms are considered to be advanced, as compared with the naked seeded Gymnosperms ( the Cycads, Pines, Podocarpus and our Widdringtonias ). Angiosperms far exceed in number and structure all other major groups of living plants. More than 200,000 species have been named and classified. The basic food supply of the world is derived from the seeds and fruits of Angiosperms. Fibers, wood, drugs and other products of great economic value also come from flowering plants.

The origin of the Angiosperms is a subject for huge and heated debate. Known fossil records have not really been able to lead us to the origin of these plants. Fossilized wood only provides fragmentary evidence that Angiosperms had reached a high stage of morphological specialization by the Middle Cretaceous Period. The evidence that is available supports the theory that Angiosperms developed over an extremely long period of time. The reason for the lack of fossil records could also possibly be found in the theory that Angiosperms developed in upland areas, i.e., in regions most unlikely for the preservation of fruits, flowers, leaves, wood and pollen. If this is true we may search in vain for tangible fossil records of truly ancient and primitive Angiosperms.

PLANT EVOLUTION

In the July National Geographic Magazine there is an interesting article on plant evolution as currently being postulated by paleobotanists based on DNA analysis rather than morphological features. Written in a 'popular' journalistic style it covers activities about which we seldom hear. Angiosperms, which we think of and know as flowering plants, are pushed back to 13O million years on fossil record and which are defined not by flowers but by enclosing seed in their carpels. The four earliest flowering families are apparently Amborellaceae ( a mono-

specific species on New Caledonia ),Nymphaeaceae, Illiciaceae and the Magnoliids followed by Monocots and Eudicots which include almost all the genera we call Dicots. The article also contains an excellent photograph of Kokerboom near Nieuwoudtville.

BABIANA GERMAN MEASLES

Rumour has it that one of the several newly discovered species of Babiana to be published in the work now in progress will rejoice in the name rubella. If we believed in sympathetic medicine we would have to warn any enceinte member not to grow this species ; a pity because it is very pretty and fragrant. The name comes from the Latin rubellus meaning reddish.

A SUGGESTED GROWING MEDIUM

Most 15 cm pots have an actual depth of 12 cm. Fill the bottom 21/2 cm with stone chips and cover this with 61/2 cm of course mixture. Press down level. Cover with 2 cm of fine mixture and press down level again. Place pot in a basin of water till the soil is moist. Set aside to drain surplus water. Now sprinkle on the seed. Place several pots in a box with a depth of about 18 cm with a layer of gravel in the bottom so that the pot drainage holes are not blocked by the floor of the box. Cover the box with a glass pane. You can use film but you have better control with glass. Tip the condensed drops on the glass each night and morning into the box, but NOT into the pots. No further watering needed. Ideally on even temperature of about 13C

so keep out of hot sun and shelter from cold nights. Course mix is large grain sand and sifted humus, 4 or even 5:1. Fine mix is fine sand and finely crumbled humus, 4 or even 3:1.

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