Family: - FabaceaeNames:
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.
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.
Leaves:Three leaflets (trifoliate) with the stalk of the central leaflet longer than those of the side leaflets.
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.
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.
Seed Biology and Germination:Vegetative Propagules:
Origin and History:Mediterranean, Southern Europe.
Distribution:ACT, NSW, NT, QLD, SA, TAS, VIC, WA.
Soil:Prefers alkaline soils.
Detrimental:Weed of crops.
Toxicity:Not recorded as toxic.
Management and Control:Chlorsulfuron, metsulfuron or triasulfuron herbicides provide high levels of control in cereal crops. Clopyralid can be used in Canola.
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:
Plants of similar appearance:Clovers (Trifolium species) usually have the central leaflet on a stalk the same length as the side leaflets.
References:Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P458. Diagram.
Acknowledgments:Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.