Background

Lucerne is an erect growing, perennial legume. It has a deep taproot that allows it to extract water from deeper soil layers and consequently has greater tolerance to moisture stress than most pasture species.

Most cultivars in NZ are winter dormant. Recently, more winter active cultivars have been sold, however, while they can start growing a week or two earlier into spring and later into autumn, in general, their persistence has been poorer than winter dormant types.

Lucerne in Farm Systems

Cool season growth is significantly less than ryegrass, but warm season growth is significantly better, as is its feed quality through late spring and summer. Because of this lucerne can be used to complement other pastures within a farm system. Under irrigation, pure swards of lucerne can grow 21 t DM/ha/year, although yields are most often less because the species is sown in summer dry areas where growth is limited by rainfall. Lucerne is also often made into high quality hay, to be used in dry summer and cold winter regions. It is increasingly ensiled to produce a protein rich supplement for dairy cows.

Lucerne Persistence

The species does not reseed itself easily and can persist from 5-8 years or more, depending on grazing management and climate. In general, a period of prolonged growth and potential flowering (6-8 weeks or up to 50% of stems with flowers) during February/ March each year encourages the build-up of root reserves for the following spring and improves stand persistence. Flat weeds, such as dandelions and annual grasses, tend to invade older, thinning stands and need to be controlled to help stands persist.