Snail medic

NOTE: The information in this Agnote must be read in conjunction with Introduction to selecting and using pastures in NSW, which covers information on areas of adaptation, sources of variability, species mixtures, and important issues related to animal health and the conservation of native vegetation.
Pasture type and use Winter/spring growing annual legume. Dryland grazing and crop rotation.
Area of adaptation Mainly in the North West and Central West Slopes and Plains.
Min. average annual rainfall 400 mm (southern NSW) to 500 mm (northern NSW)
Advantages
  • Persists in areas considered too arid for sub clover.
  • Large pods readily eaten by sheep.
  • Spineless pods.
  • High quality grazing.
  • Helps maintain nitrogen fertility in cropping rotations.
Disadvantages
  • Generally inferior to other temperate legumes in higher-rainfall areas.
  • Regeneration sometimes poor.
  • Lush and/or pure stands can cause animal health problems.
Soil requirements Prefers neutral–alkaline and heavier soils. Better regeneration on self-mulching soils. Will not tolerate exchangeable soil aluminium >10%.
Varieties Select varieties on the basis of maturity, yield and persistence.
  • Early flowering: Sava Silver
  • Mid flowering: Essex
  • Late flowering: Kelson
Sowing rates:
- as only species 4–7 kg/ha
- in mixtures 3 kg/ha
Sowing time Autumn for all districts.
Companion species Lucerne (winter-active) in appropriate soil types.
Inoculation Medic (or group AM).
Major nutrient deficiencies Usually phosphorus, sulfur in some areas, occasionally zinc and molybdenum.
Main insect pests Redlegged earth mite, blue oat mite, lucerne flea, spotted alfalfa aphid, bluegreen aphid, pea aphid.
Main diseases Root rot, alfalfa mosaic virus, phoma.
Management Once established can be continuously grazed. Avoid overgrazing at seed-set in initial year to build seed reserves.
Livestock disorders of particular note Photosensitisation in horses; occasionally red gut in sheep; frequently bloat in cattle.
Additional tips
  • Sowing without a cover crop greatly improves establishment.
  • Good medic establishment has been achieved in south-west NSW using a seed spreader mounted on a prickle chain unit.
Further information
  • Agfact P2.1.12 Pasture legumes for low rainfall environments.
  • Agfact P2.5.11 Medic pastures.
  • Agfact P2.5.26 Murex medic.
  • Weed control in lucerne and pastures 2004.

Acknowledgments

Advice on livestock health disorders was provided by Dr Chris Bourke, Principal Research Scientist, NSW Agriculture, Orange. His contribution is gratefully acknowledged.

Photo: Mary-Anne Lattimore, NSW Agriculture, Yanco.