Leucospermum cordifolium

We are nearing the end of the flowering season of one of our favourite indigenous garden plants – the Pincushion, Leucospermum cordifolium.   One of the easiest of the Proteaceae to cultivate, it forms a neat bush, flowers over a long period and is wonderful for the vase or mass displays.

Yet not all is well with this familiar beauty.  “How come?” you may ask, ” We see it everywhere, in parks and gardens, on road verges and on the mountain slopes.” Amazingly, the latest Red List describes this plant as Near Threatened!

The justification for this is a 30% reduction in population over the past 60 years, as a result of habitat loss and extensive picking of planted and wild plants.  This is the most popular horticultural Pincushion and many cultivars are available.  These are planted extensively in protea orchards adjacent to natural stands throughout its range.  Contamination of natural gene pools is thus a major concern.

And this is exactly what is happening in Fernkloof.  When the nature reserve was first proclaimed, the first Curator, Mr Harry Wood, was instructed by the municipality to establish a garden using plants from the Caledon Division.  He duly planted stands of many species of Proteaceae and other plants.  Many of them thrived and I vaguely remember, as a newcomer to Hermanus in the late 1960’s, healthy stands of Protea coronata, P. nerifolia and Leucospermum cordifolium, amongst others.  Shortly after that a fire swept through the area and many of the species disappeared – but not the Pincushions.  They seem to love fire and gradually over the years they have spread ever outwards from the original nucleus, spurred on by periodic fires.

That should not be a problem, you  might say.  Fernkloof obviously suits them well and they are beautiful to look at.  But there is a hidden danger.  These plants are of unkown genetic origin.  If the species did not occur in Fernkloof at all, then all might be well.  BUT there are actually two known populations of Leucospermum cordifolium native to Fernkloof.  One has recently been discovered on the northern slopes at Kantoors Kloof, however, I cannot comment on that, as I have not seen the plants.

The other population, on the slopes above Northcliff, has been known for many years.  I remember it being pointed out to me by the late Dr Ion Williams, who considered it “rather special”.  It seems to grow more slowly than some other forms and takes longer reach flowering size.  It also seems to set very little seed, yet it has managed to recover after a number of fires which have swept through the population in the 40 odd years that I have known it.  It has maintained its fairly small population size over the years and has not spread beyond the narrow confines of its preferred habitat.

In contrast,  the introduced variant has spread by leaps and bounds, particularly after each fire.  The fire of 2008 has seen a fairly large expansion of its range in a westerly direction.  It has now nearly reached Klipspringer and plants flowered for the first time this year.  So how long will it take to reach and contaminate our “indigenous” population?  How far does a bird fly? Can we determine a cut-off point and say, “so far and no further”, or do we simply accept that in due course the two will meet and that the genetic integrity of our local population is doomed?

 

Ons nader die einde van die blomseisoen van een van ons gunsteling inheemse tuinplante – die Speldekussing Leucospermum cordifolium. Dit is een van die maklikste Proteaceae om te kweek; dit vorm ‘n netjiese bos, blom oor ‘n lang tydperk en is fantasties in ‘n blompot of vir massavertonings. Nie alles gaan egter goed met hierdie bekende skoonheid nie. Hoe dan so?  mag jy vra – ons sien dit dan oral, in parke en tuine, op padreserwes en teen die berghange. Verbluffend beskryf die jongste Rooilys hierdie plant as Subbedreig!

Regverdiging hiervoor is ‘n 30% afname in populasie oor die afgelope 60 jaar as gevolg van habitatverlies en uitermatige pluk van aangeplante en wilde plante. Hierdie is die populêrste tuinbou- speldekussing waarvan vele kultivars beskikbaar is. Die hele reeks word wyd in Proteaboorde aangrensend aan die natuurlike stande geplant. Besoedeling van die natuurlike genebank is dus ‘n ernstige saak.

En dit is presies wat nou in Fernkloof gebeur. Toe die natuurreservaat aanvanklik geproklameer is, het die eerste Kurator , meneer Harry Wood, opdrag van die munisipaliteit gekry om ‘n tuin te vestig met plante van die Afdeling Caledon. Hy het dienooreenkomstig stande van vele Proteaceae – spesies en ander plante geplant. Baie van hulle het gedy en ek kan vaagweg, as nuweling in Hermanus tydens die laat sestiger jare, onder andere gesonde stande  Protea coronata, P. nerifolia en Leucospermum cordifolium onthou. Kort daarna het ‘n vuur deur die gebied gewoed, en baie van die spesies het verdwyn – maar nie die Speldekussings nie. Hulle hou blykbaar daarvan om te brand en het, aangespoor deur periodieke brande, geleidelik oor die jare uitgesprei vanaf die oorspronklike kern.

Jy mag sê dat dit geen probleem hoef te wees nie. Hulle aard klaarblyklik baie goed in Fernkloof  en hulle is pragtig om na te kyk. Maar daar skuil tog ‘n verborge gevaar. Hierdie plante kom van onbekende genetiese oorsprong. Indien hierdie spesies nog nooit vantevore in Fernkloof voorgekom het nie, is alles wel. MAAR daar is eintlik twee bekende inheemse Leucospermum cordifolium-bevolkings in Fernkloof. Een is onlangs teen die noordelike hange by Kantoorskloof ontdek. Aangesien ek hierdie plante nog nie gesien het nie, kan ek geen kommentaar daaroor lewer nie.

Die ander bevolking, teen die hange bokant Northcliff, is jare reeds bekend. Ek onthou dat oorlede dr Ion Williams, wat dit as “redelik besonders” bestempel het, dit aan my uitgewys het. Die groeiproses is blykbaar stadiger as sommige ander vorms, en dit neem langer om blomgrootte te bereik. Dit blyk ook baie min saad voort te bring en tog het dit daarin geslaag om,  selfs na ‘n aantal brande wat in die ongeveer veertig  jaar wat ek dit ken, deur die bevolking gewoed het,  te herstel.  Die redelik klein bevolking het sy grootte deur die jare behou en het nie buite die grense van die beperkte verkose gebied versprei nie.

In skerpe teenstelling hiermee het die ingekome variant, veral na elke brand, met rasse skrede versprei. In die 2008-brand was ‘n redelik groot uitbreiding van sy reeks in ‘n westelike rigting waarneembaar. Dit het nou amper so ver as Klipspringer gevorder en plante blom vir die eerste keer hierdie jaar. Dus, hoe lank sal dit neem om ons “inheemse” bevolking te bereik? Hoe ver vlieg ‘n voel? Kan ons ‘n afsnypunt bepaal en sê “ tot hiertoe en nie verder nie” of neem ons eenvoudig aan dat die twee mettertyd sal ontmoet en dat die genetiese integriteit van ons plaaslike bevolking gedoem is?

Text by Lee Burman,  January 2014.   Translated by Andre van der Spuy.  Photos by Sandy Jenkin

About roncorylus

He who wants the kernel must crack the nut
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One Response to Leucospermum cordifolium

  1. Anina Lee says:

    Thanks Lee and Sandy for a thought-provoking article. Excuse my ignorance, but someone will have to show me the difference between the local variety and the introduced one. Anina

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