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We seek it here. we seek it there ...
SouthAfrica'sScarletPimpernelIn search ofGladiolus stokoei
South Africa's Scarlet Pimpernel, Gladiolus stokoei. Photo: John Manning.
10by John Manning, Compton Herbarium, South African National Biodiversity Institute
ABOVE: Colour plate 1004 accompanied theoriginal description of Gladiolus stokoei by G. J.Lewis in Flowering Plants of Africa 26 (1947),and was reproduced from an original watercolour painted by Lewis herself. This copy of theplate, now held at the Compton Herbarium, wasThomas Stokoe's own.
138 September 2006 Veld&Flora
If a single group of plants can justlylay claim to the crown in a familyrenowned throughout the world for thebeauty and elegance of its many spe
cies, then that group is the genusGladiolus. With more than 255 knownspecies, it is rivalled in richness onlyby Moraea in the south, and by Iris in
the Northern Hemisphere. The greatmajority of gladiolus species are foundnaturally only in Africa south of theSahara, with their centre of diversity in
temperate southern Africa, and moreparticularly the extreme south-west.
This biological hotspot at the southerntip of the continent, known to botanistsas the Cape Floral Region, is home tothe richest temperate flora in the world.
Dominated by evergreen shrubs withleathery, often small leaves, the fynbos vegetation that characterizes theregion is also uniquely blessed withbulbous plants. The various types ofbulbs that abound here account forupwards of 16% of all the species in the
region. This is several times the proportion recorded in other bulb-rich regions
of the world. Numbering prominentlyamong them are more than 100 speciesof gladiolus.
Species of gladiolus were among
the very first native plants to attractthe attention of European botanistsand travellers to South Africa. Someof the earliest recorded observationswere made during Commander Simonvan der Stel's expedition to the cop
per mines near Springbok in 1685.This expedition, which left the Fortof Good Hope on the morning of 25August of that year, included the art
ist and apothecary Heinrich Claudius,who was tasked with illustrating plantsand animals of interest. His drawings ofGladiolus caryophyllaceus and G. spe
ciosus are among the first made of any
South African gladiolus species. By theearly 1700s scarcely a half-dozen or so
Cape gladioli were known to Europeanbotanists. Not surprisingly, most ofthese were species that grew (and stilldo, although in much diminished num
bers) around Cape Town itself. By 1750the number of gladiolus species thathad been discovered in the south-west
ern Cape had crept up to a dozen butthereafter their discovery accelerated
markedly. Over the next two centuriesnew species of gladiolus were beinguncovered at the rate of around twentyspecies every fUty years. Two especiallyproductive periods span the second
half of the eighteenth century and thefIrst half of the twentieth. The fIrst ofthese coincides with the presence in
the Cape of the Swedish botanist, CarlPeter Thunberg, justly known as theFather of South African Botany andresponsible for the discovery of no lessthan thirteen new species of gladi
olus. The second period of exceptionalbotanical activity followed the estab
lishment in the first decades of thecentury of both the University of CapeTown, with two chairs of Botany, andKirstenbosch Botanical Gardens. Theactivities of these two institutions stimulated an interest in botany throughoutthe south-western Cape, encouraging
many residents to explore the mountains and valleys around them for new
or unusual plants.Thomas Pearson Stokoe (1868-1959)
was one of those who responded to the
enthusiasm for natural history that wasprevalent in the first half of the cen
tury - with significant results for Capebotany. Joining the Mountain Club in1913, he explored the mountains of thesouth-western Cape for the next forty
five years, venturing onto their slopesright up to the time of his death at theage of ninety-one. During this time hecollected many new species and is com
memorated in the names of some thirtyof them, including Brunia stokoei, Ericastokoei, Mimetes stokoei and Proteastokoei. One of the most spectacular,however, is Gladiolus stokoei.
This extraordinary species was firstcollected by Stokoe in the autumn of1930 on the farm Oubos, which runsup the southern foothills of Pilaarkop,the highest peak in the eastern reach
es of the Riviersonderend Mountains.Little more than 80 km in length,and reaching over 1 500 m above sealevel, the Riviersonderend Mountains
project as a short spoke from the greatmountain complex that forms the hubof the Cape Fold Mountains. Their precipitous southern slopes overlook therolling forelands of the Overberg andthe river at their feet from which they
take their name. They are sunderedfrom neighbouring mountain ranges bylow-lying valleys or plains on all sides,
and millennia of isolation have encouraged the evolution of a host of distinctspecies that are found only on their
upper slopes. Gladiolus stokoei is oneof these.
Stokoe knew at once that he haddiscovered something unusual, andimmediately set about sketching theflowers on the mountainside where
he had found them. These drawingsare preserved, along with his original collection, in the Bolus Herbariumat the University of Cape Town. Thefirst trained botanist to see his collec
tion was Harriet Margaret Louisa Bolus(1877-1970), who had been appointedas Curator of the Bolus Herbarium in1903 by her great-uncle, Harry Bolus(1834-1911) himself. She immediately
appreciated the significance of Stokoe'sdiscovery, and expressed her intention of describing it as a new speciesby annotating the herbarium sheet 'G.
stokoei L. Bolus'. Unfortunately some
thing must have intervened and it fellto one of her students, GwendolyneJoyce Lewis, to name the species in1947. The stimulus for this was once
again provided by Stokoe, who in 1945returned to Pilaarkop and re-collectedthe species. This collection formed thebasis for the colour illustration, paintedby Lewis herself, which accompaniedthe description. The species then dis
appeared from sight until 1972, whenGeorges Delpierre and Neil du Plessisre-visited the type locality in searchof it during the preparation of theirhandbook The winter-growing gladioli ofSouth Africa (Tafelberg 1973).
It was a similar quest that ledPeter Goldblatt and myself to contact
Professor Delpierre in the mid 1990s.At that time we were immersed in the
writing of Gladiolus in southem Africa(Fernwood Press 1998) and also wishedto fmd G. stokoei in order to have itillustrated. Out of 160 South African
species that we recognized in this work,just ten eluded us. G. stokoei was oneof these. Three times over the following few years we hiked up the slopes ofPilaarkop in search of it, but although
we encountered other local rarities likeEndonema retzioides, not a trace ofStokoe's gladiolus could we find, andthe book appeared without an illustration of the elusive plant. By now I hadgiven up hope of seeing the species.Plants introduced into cultivation from
Delpierre's collection had disappeared
and so too the immediate incentive toclimb the forbidding slopes.
In April this year a group of usboarded a helicopter on a quest to relo
cate a mysterious Nivenia species thathad been photographed high on theRiviersonderend Mountains the previous year. Within an hour of lifting offfrom Cape Town Airport we had beenwhisked over the top of the moun
tains and deposited on a spur runningdown from the summit of Pilaarkop. I
searched through several rocky outcrops that protruded from the swathethat mantled the spur without success, and disappointment was settingin when a flutter of scarlet among the
boulders and vegetation attracted myeye. A solitary stem, bearing two flowers, protruded from alongside the arching leaves of bergpalmiet, Tetraria thermalis. Cupped like a perfect tulip, the
brilliant red petals were burnished withgolden flecks in the raking sunlight.Gladiolus stokoei had been found againafter a second lapse of thirty years. !iiJ
ABOVE: Gladiolus stokoei flowering in theRiviersonderend Mountains. Photo: John Manning.
BELOW: Theforbidding slopes ofthe RiviersonderendMountains from the air. Photo: John Manning.