Snail Medic
Medicago scutellata (L.) Mill.

Synonyms -

Family: - Fabaceae

Names:

Other Names:

Snail Clover

Snail Trefoil

Summary:

A low lying to ascending, very hairy, annual medic with trifoliate leaves with oval, toothed leaflets without markings and the central leaflet on a longer stalk. The burr is a coiled, spineless, flat, papery pod that looks like a snail and is produced from yellow orange, pea type flowers.

Description:

Cotyledons:

Two. Oval, large. Tip round. Sides convex to parallel. Base tapered to squarish. Surface hairless. No petiole.

First leaves:

Oval to triangular. Tip rounded to pointed. Edges smooth to scalloped. Base squarish to tapered. Hairy on the lower surface and edges. Long hairy petiole.

Second and later leaves trifoliate.

Leaves:

Three leaflets (trifoliate) with the stalk of the central leaflet longer than those of the side leaflets.

Stipules - Prominent, lance shaped, 10 mm long, 2-3 tiny teeth. Hairy.

Petiole - Medium, about the same length as the leaf.

Blade - Of leaflet oval to triangular or egg-shaped. Tip pointed. Edges sharply toothed. Base tapered. Hairy with glandular hairs.

Stems:

Long, low lying or upward bending. Very hairy.

Flower head:

1-3 flowers on an awned stalk shorter than the leaves.

Flowers:

Yellow-orange to yellow pea type.

Ovary -

Sepals -

Petals - Yellow, often with brown streaks on the standard.

Stamens -

Anthers -

Fruit:

Almost globular pod with 5-8 anticlockwise, cup shaped, coils with lower coils partially overlapping those above, resembling a snail, 10-12 mm long by 12-15 mm wide. Downy, smooth, spineless. Pod has about 10 seeds.

Seeds:

Yellow to brown, kidney shaped, 4-6 mm long by 2-3 mm wide. Tip round. Edges concave or convex. Base round. Surface shiny and hairless.

Roots:

Taproot with nitrogen fixing nodules.

Key Characters:

Biology:

Life cycle:

Annual. Seeds germinate from autumn to winter.

Physiology:

Reproduction:

By seed.

Flowering times:

Spring.

September to November in SA.

Seed Biology and Germination:

Vegetative Propagules:

Hybrids:

Allelopathy:

Population Dynamics and Dispersal:

Spread by seed and intentional plantings.

Origin and History:

Mediterranean, Southern Europe.

Distribution:

ACT, NSW, NT, QLD, SA, TAS, VIC, WA.

Habitats:

Climate:

Temperate to sub tropical

Soil:

Prefers alkaline soils.

Plant Associations:

Significance:

Beneficial:

Fodder

Detrimental:

Weed of crops.

Toxicity:

Not recorded as toxic.

Symptoms:

Treatment:

Legislation:

None.

Management and Control:

Chlorsulfuron, metsulfuron or triasulfuron herbicides provide high levels of control in cereal crops. Clopyralid can be used in Canola.

Tolerant to grazing.

Thresholds:

More than 20 plants/m2 is usually worth controlling in cereal crops.

Eradication strategies:

In bushland situations, Logran® at 40g/ha provides reasonably selective control.

Herbicide resistance:

None reported. It is relatively tolerant to glyphosate.

Biological Control:

Related plants:

Barrel Medic. (Medicago truncatula)

Black Medic (Medicago lupulina)

Burr Medic (Medicago polymorpha, Medicago hispida)

Button Medic (Medicago orbicularis)

Calvary Medic (Medicago intertexta)

Cutleaf Medic (Medicago laciniata)

Disc Medic (Medicago tornata)

Gama Medic (Medicago rugosa)

Lucerne (Medicago falcata ssp. sativa)

Lucerne (Medicago sativa)

Murex Medic (Medicago murex)

Small leaved Burr Medic (Medicago praecox)

Snail Medic (Medicago scutellata)

Spotted Medic (Medicago arabica)

Strand Medic (Medicago littoralis)

Woolly Burr Medic (Medicago minima)

Yellow Lucerne (Medicago falcata)

Plants of similar appearance:

Clovers (Trifolium species) usually have the central leaflet on a stalk the same length as the side leaflets.

Melilotus species

Oxalis species usually have a bitter taste.

Trefoils

References:

Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P458. Diagram.

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

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

Harden, Gwen J. (1991). Flora of NSW. (Royal Botanic Gardens, Sydney). Volume . P. Diagram.

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). P154.

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). #638.17.

Moerkerk, M.R. and Barnett, A.G. (1998). More Crop Weeds. R.G. and F.J. Richardson, Melbourne. P91. Diagrams. Photos.

Acknowledgments:

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