Carpobrotus edulis

Taxobox
name = "Carpobrotus edulis"


image_width = 240px
regnum = Plantae
divisio = Magnoliophyta
classis = Magnoliopsida
ordo = Caryophyllales
familia = Aizoaceae
genus = "Carpobrotus"
species = "C. edulis"
binomial = "Carpobrotus edulis"
binomial_authority = (L.) N.E. Br

"Carpobrotus edulis" is a creeping, mat-forming succulent species and member of the Stone Plant family Aizoaceae, one of about 30 species in the genus "Carpobrotus". It is also known as Ice Plant, Highway Ice Plant, Pigface or Hottentot Fig and in South Africa as the Sour Fig, on account of its edible fruit. It was previously classified in genus "Mesembryanthemum" and is sometimes referred to by this name. The species is native to South Africa but is naturalised in many other regions throughout the world.

"Carpobrotus edulis" is easily confused with its close relative, the more diminutive and less aggressive "Carpobrotus chilensis" (sea fig), and the two species hybridize readily throughout their ranges in California. The large 2.5 to 6 inch diameter flowers of "C. edulis" are yellow or light pink, whereas the smaller, 1.5 to 2.5 inch diameter "C. chilensis" flowers are deep magenta.

Invasiveness

In several parts of the world, notably Australia, California and the Mediterranean, all of which share a similar climate, the Ice Plant has escaped from cultivation and has become an invasive species. The Ice Plant poses a serious ecological problem, forming vast monospecific zones, lowering biodiversity, and competing directly with several threatened or endangered plant species for nutrients, water, light, and space (State Resources Agency 1990).

United States

In the early 1900s "C. edulis" was brought to California from South Africa to stabilize soil along railroad tracks and was later put to use by Caltrans for similar purposes. Thousands of acres were planted in California until the 1970s. It easily spreads by seed (hundreds per fruit) and from segmentation (any shoot segment can produce roots). Its succulent foliage, bright magenta or yellow flowers, and resistance to some harsh coastal climatic conditions (salt) have also made it a favoured garden plant. The Ice Plant was for several decades widely promoted as an ornamental plant, and it is still available at some nurseries. Ice Plant foliage can turn a vibrant red to yellow in color.

The Ice Plant is still abundant along highways, beaches, on military bases, and in other public and private landscapes. It spreads beyond landscape plantings and has invaded foredune, dune scrub, coastal bluff scrub, coastal prairie, and most recently maritime chaparral communities. In California, the Ice Plant is found in coastal habitats from north of Eureka, California, south at least as far as Rosarito in Baja California. It is intolerant of frost, and is not found far inland or at elevations greater than approximately 500 feet (150 m).

Mediterranean

On the Mediterranean coast, "Carpobrotus" has spread out rapidly and now parts of the coastline are completely covered by this invasive species. Moreover, it has been shown that another invasive species, the black rat, enhances the spreading of the ice plant through its feces [http://www.issg.org/database/species/ecology.asp?si=1010&fr=1&sts= "Carpobrotus edulis" in the Global Invasive Species Database] . As the ice plant represents a food resource for the rat, the invasive species benefit from each other (invasive mutualism).

Growth

Ice Plants grow year round, with individual shoot segments growing more than three feet (1 m) per year (D’Antonio 1990b). Ice Plants can grow to at least 165 feet (50 m) in diameter. Flowering occurs almost year round, beginning in February in southern California and continuing through fall in northern California, with flowers present for at least a few months in any given population. Seed production is high, with hundreds of seeds produced in each fruit. The fruit is edible. In South Africa the Sour Fig's ripe fruit are gathered and either eaten fresh or made into a very tart jam.

Removal of Plant

Control of Ice Plants can be attempted by pulling out individual plants by hand, or with the use of earth-moving machinery such as a skid-steer or tractor, though it is necessary to remove buried stems, and mulch the soil to prevent re-establishment. For chemical control, glyphosate herbicides are used. Because of the high water content of shoot tissues, burning of live or dead plants is not a useful method of control or disposal.

Uses

Its leaves are edible, as are its fruit, as with other some members of the Aizoaceae family.

It was used in California to stabilize soil around railroad tracks, as discussed above.

References

External links

* http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=25&surveynumber=182
* [http://davesgarden.com/pf/go/2024/index.html Carpobrotus edulis at PlantFiles]
* http://www.hear.org/pier/species/carpobrotus_edulis.htm