Iceplant

Mesembryanthemum crystallinum L.

Synonyms - Cryophytum crystallinum, Gasoul crystallinum.

Family: Aizoaceae.

Names:

Common Iceplant.

Summary:

A low lying, annual or biennial herb covered with large glistening warts on the leaves and stems and with white flowers that have many long thin petals.

Description:

Cotyledons:

Two. Diamond shaped, with glistening water filled pimples. Tip pointed to rounded. Sides straight and angular. Base squarish to indented or clasping. Surface hairless.

First leaves:

Opposite, fleshy, diamond shaped with glistening water filled pimples. Tip pointed. Hairless.

Leaves:

Opposite but maybe alternate on flowering branches. Leaves fall before flowering.
Stipules - None.
Petiole - Short, broad, stem clasping and 3 nerved.
Blade - Egg shaped to triangular or heart shaped, flat with wavy edges, thick, fleshy with water filled pimples or warts that appear scale like when dry. Basal leaves 60-120 mm long x 80 mm wide. Hairless. Tapers to a pointed tip.
Stem leaves - Alternate or opposite, egg shaped and 20-40 mm long. Leaves on flowering stems are alternate.

Stems:

Fleshy, pimply, round, stout, low lying, up to 200 mm long and 150 mm high, branched, often reddish, forms a mat. Hairless.
Flower stem - has alternate leaves

Flower head:

Single flowers on stalks on the ends of branches or opposite a leaf.

Flowers:

White. Many thin petals.
Ovary - Half inferior, 5 cells, 3-4 mm long, 5 ribbed. 5 erect thread like styles, 3-4 mm long.
Sepals - 5-10 mm long with 5 lobes. 3 outer lobes are flat topped and 3-5 mm long. 2 inner ones are smaller.
Petals - White, many, thin and narrow, in several rows, much longer than sepals, 12-15 mm long.
Stamens - Many, arising at various heights in the tube, fewer and shorter than the staminodes. Many white, thread like staminodes, 13-15 mm long, joined into a tube for more than half their length.
Anthers - Erect, 0.7-1 mm long.

Fruit:

5-12 mm wide capsule, opening when moistened, in a star shape to expose 5 spreading, bony grooved partitions and membranous flaps terminating the valves and folding inwards to cover the seed until they are ejected.

Seeds:

Many, spherical, small, 1 mm, flattened, brown with a network pattern.

Roots:

Taproot.

Key Characters:

Plant densely warty. Petals longer than sepals. Sepals not distinctly keeled.

Biology:

Life cycle:

Annual or biennial. Germinates autumn to winter mainly. Flowers late winter to summer. Most plants die with the onset of drought but in moist situations they may continue to grow for another season.

Physiology:

Reproduction:

By seed.

Flowering times:

Spring to early summer in western NSW.
October to December in SA.
October to December in Perth.

Seed Biology and Germination:

Vegetative Propagules:

None.

Hybrids:

Allelopathy:

Alters soil chemistry.

Population Dynamics and Dispersal:

Spread by seed.
Often in patches.

Origin and History:

South Africa. Mediterranean.

Distribution:

NSW SA, TAS, VIC, WA.

Courtesy Australia's Virtual Herbarium.

Habitats:

Climate:

Temperate. Mediterranean.

Soil:

Most abundant on saline and coastal soils, sands, loams and granite outcrops.

Plant Associations:

In many communities including Mallee and Belah-rosewood. Often around the edges of salt lakes.

Significance:

Beneficial:

Ornamental.
Honey plant.

Detrimental:

Weed of roadsides, crops, pastures and islands.
Unpalatable and rarely eaten.

Toxicity:

May cause oxalate poisoning but field cases are not common.
Most cases occur in summer.

Legislation:

None.

Management and Control:

Thresholds:

Eradication strategies:

Herbicide resistance:

Biological Control:

Related plants:

Angled Iceplant (Mesembryanthemum aitonis) has fewer glistening pimples, the petals are about the same length as the sepals and it flowers earlier.
Slender Iceplant (Mesembryanthemum nodiflorum) is an annual, more upright and with linear leaves.

Plants of similar appearance:

References:

Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P337. Diagram.

Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992). Plants of Western New South Wales. (Inkata Press, Melbourne). P294. Photo.

Gilbey, D. (1989). Identification of weeds in cereal and legume crops. Bulletin 4107. (Western Australian Department of Agriculture , Perth). P34. Photos.

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). P76-77. Photo.

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

Lazarides, M. and Hince, B. (1993). CSIRO handbook of economic plants of Australia. (CSIRO, Melbourne). #817.2.

Marchant, N.G., Wheeler, J.R., Rye, B.L., Bennett, E.M., Lander, N.S. and Macfarlane, T.D. (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). P78.

Wilding, J.L. et al. (1987). Crop weeds. (Inkata Press, Melbourne). P37.

Acknowledgments:

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