Lucerne (Medicago sativa L.) is a perennial legume and a valuable crop worldwide, with approximately 3.2 million hectares sown in Australia.
Lucerne has a deep taproot which can extract available water from the soil profile and also has high water use efficiency, making it a very drought tolerant species.
Lucerne can fix its own nitrogen and is proportional to the foliage grown (approximately 25kg N/t above ground dry matter).
It is often being referred to as the ‘King of Fodders’, because of its high nutritional quality, high yield, persistence under dry conditions, ability to fix atmospheric nitrogen and flexibility of being a dual-purpose crop for both grazing and hay, or for specialty hay and silage crops.
The question often asked is ‘why isn’t everyone growing it?’ The role it can play and suitability on each individual farm will be different from region to region. While there are some perceived limitations to growing lucerne, sound agronomic advice and practice during paddock selection, preparation, establishment and ongoing management for the life of a stand will go a long way in mitigating many of these.
Numerous studies have shown the benefits of lucerne-based pastures for improvement in animal production in Australia:
Persistence of a stand is affected by several factors which include dormancy group, grazing and/or hay management, soil fertility, drought and weed invasion. Choosing the right lucerne is about selecting the right characteristics for the environment and management system required, with the aim to ensure the stand produces well for as long as it is needed.
As lucerne relies on stored energy in its roots to regrow new foliage following grazing/cutting, a simple grazing rotation with minimum recovery periods of 35 days (dependent on seasons) and short grazing periods (5-7 days) will ensure a good compromise between quality, yield, animal safety and persistence. However, often the ‘ideal’ grazing management techniques can be difficult due to the size of paddocks or livestock numbers, infrastructure and grazing time required during dry periods (when the only feed available may be the lucerne paddocks). These factors mean that at times lucerne can be over-grazed and stand life depleted. However, the release of grazing tolerant lucerne cultivars, which have been developed to withstand continuous and less than ideal grazing practices, offers a significant benefit to producers.