Hottentot Fig

Carpobrotus edulis (L.) L.Bolus

Synonyms - Mesembryanthemum edule

Family: Aizoaceae

Names:

Carpobrotus means edible fruit.
Edulis means edible referring to the fruit.

Other Names:

Highway Iceplant (USA).
Ice Plant (NZ)
Pigface

Summary:

A succulent, perennial creeper or low lying shrub up to 20 m in diameter and 1 m tall. The leaves are paired, triangular in cross section with slightly serrated edges and about as big as your little finger. The flowers are initially yellow and turn pink with age, 7.5-10 cm diameter and with many narrow "petals".

Description:

Cotyledons:

Two.

First leaves:

Leaves:

Opposite. Joined at the base.
Stipules - None.
Petiole - None.
Blade - Dull to dark green often reddish, triangular, succulent, smooth, and 40-140 mm long x 8-17 mm wide x 7-16 mm thick tapering to an acute tip. Slightly concave surfaces. Keel with tiny teeth at least near the tip. Hairless.

Stems:

Stout, usually up to 2 m long, occasionally up to 20 m x 8-13 mm thick, creeping, woody at the base, 2 angled. Hairless.

Flower head:

Single flowers in leaf axils. Flower stalk 10-20 mm long, slightly flattened with acute, toothed edges

Flowers:

Pale yellow turning pinkish orange with age, 75-100 mm diameter x 20-25 mm long. Flowers close in dull conditions. Bisexual.
Ovary - More or less inferior and joined to the perianth tube.
Styles - 8-11, 7-15 mm long.
Calyx - 5 lobes, longest lobes 20-45 mm long with a finely toothed keel. Inner lobes dotted throughout.
Petals - absent. Staminodes are somewhat petal like.
Stamens - 400-600, yellow. Filament usually yellowish or tinged with pink above the hairs, up to 12 mm long.
Staminodes - about 125 staminodes that are initially yellow becoming pink with a white base, 30-35 mm long x 1.5-2.5 mm thick.
Anthers - Yellow, 1.8-3.5 mm long, 2 celled.

Fruit:

Dull yellow, succulent, fig like capsule, 40-50 mm long. Edible.

Seeds:

Brown, 1 mm long, smooth.

Roots:

Slender and shallow.

Key Characters:

Prostrate or semi prostrate shrub
Plant smooth, without papillae.
Leaves opposite, large, succulent, 3 cornered in section.
Stems not segmented and flat
Flowers solitary and axillary, 75-100 mm diameter when open.
Flowers without a cup shaped involucre.
Perianth tubular in the lower part, 4-5 lobed above.
Numerous petaloid linear staminodes outside the fertile stamens
Ovary more or less inferior and adnate to the perianth tube,
8-16 styles and ovary cells.
Placentas parietal.
Inner calyx lobes dotted throughout.
Staminodes initially yellow, becoming flesh pink.
Stamens 10-numerous, epigynous.
Fruit succulent, large, edible, indehiscent.
Adapted from B.L. Rye Flora of Perth and John Black Flora of SA.

Biology:

Life cycle:

Short lived perennial that flowers in spring and produces edible fruit in early summer. Often dies back in summer and re grows in autumn or when rains occur.

Physiology:

Reproduction:

By seed.

Flowering times:

August to October mainly in Perth.
September to November in SA.
October to February in NZ.

Seed Biology and Germination:

Fire encourages germination of seed and establishment.

Vegetative Propagules:

Stem fragments.

Hybrids:

Hybridises with some other species in this genus including the native Carpobrotus virescens.

Allelopathy:

Population Dynamics and Dispersal:

Spread vegetatively and by birds and seed eating mammals including rabbits, rats and wallabies.

Origin and History:

Coastal South Africa.
Introduced for erosion control and as an ornamental.

Distribution:

NSW, SA, TAS, VIC, WA.

Courtesy Australia's Virtual Herbarium.

Habitats:

Climate:

Temperate. Moist to very wet conditions.

Soil:

Rocky foreshores, coastal dunes, road cuttings, banks. Winter wet depressions.

Plant Associations:

Coastal scrub. Tuart and Banksia woodlands.

Significance:

Beneficial:

Ornamental. Food. Shelter. Soil stabiliser. Edible fruit. Grazing value is variable.
Herbal medicine uses for blue bottle stings, sunburn and as an antiseptic gargle.

Detrimental:

Weed of disturbed areas, roadsides.
It can form inpenetrable mats that crowd out other species.
Invasive weed of the USA.
It may hybridise with native Carpobrotus species.

Toxicity:

Not toxic.

Legislation:

None.

Management and Control:

Don't plant it for soil stabilisation close to bushland.

Thresholds:

Eradication strategies:

Isolated plants can be manually removed providing care is taken to remove buried stems. Patches can be manually removed by starting on one side and rolling it up like a carpet.
Large areas can be treated with glyphosate.
Establish other native Carpobrotus or similar species on the area to reduce the risk of re infestation.

Herbicide resistance:

Biological Control:

Related plants:

Angular Pigface (Carpobrotus aequilaterus) is very similar but has smaller lighter leaves and smaller flowers that are purplish red rather than yellow to pink and flowers a little later.
Coastal Pigface (Carpobrotus virescens) has smaller flowers with pink petals that are white at the base and the young stems are red. It is a native species.

Plants of similar appearance:

References:

Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P338. Diagram.

Bodkin, F. (1986). Encyclopaedia Botanica. (Angus and Robertson, Australia).

Everist, S.L. (1974). Poisonous Plants of Australia. (Angus and Robertson, Sydney).

Hussey, B.M.J., Keighery, G.J., Cousens, R.D., Dodd, J. and Lloyd, S.G. (1997). Western Weeds. A guide to the weeds of Western Australia. (Plant Protection Society of Western Australia, Perth, Western Australia). P76. Photo.

Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne).

Lazarides, M. and Cowley, K. and Hohnen, P. (1997). CSIRO handbook of Australian Weeds. (CSIRO, Melbourne). 204.2.

Marchant et al (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). P77.

Randall, J.M. and Marinelli, J. (1996) Invasive Plants. (Brooklyn Botanic Gardens Inc. Brooklyn). P72. Photo.

Roy, B., Popay, I., Champion, P., James, T. and Rahman, A. (1998). An Illustrated Guide to Common Weeds of New Zealand. (New Zealand Plant Protection Society). P26. Photo

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information for more information.