Grazing Tolerant Lucerne Selection Trial
May 19, 2023 All Regions
Penfield Research Station | Trial Sown 14/09/2011 | Grazed 24/11/2011 – 23/11/2016
S&W Seed company has taken the term ‘grazing tolerant’ very seriously with its selection of new lucerne material. The ability to select plant germplasm through a five-year intensive grazing trial has proven critical to giving farmers confidence in new lines coming through the S&W lucerne breeding program. The strength of this trialling model will be replicated in the future with more selections being made with this key grazing tolerance trait.
The trial protocol was established in conjunction with NSW DPI and IP Australia to give a measure of true grazing tolerance. After the lucerne was established, it was grazed every three weeks (or when grazing was required) to a residual height of about 30 millimetres.
Approximately 20 Merino wethers were used for grazing the trial each time, this was the number of animals adequate to graze the trial down within at least a three to four day period so we could manage frequent grazing events but not expose the lucerne to extended periods of set stocking.
The basis of this grazing management was to make sure the lucerne was put under frequent grazing pressure but not deliberately set stocked. In the first three-year period, the trial was grazed 32 times, and in the recent two-year period, was grazed 18 times.
Plant counts were taken initially, and results have been measured based on the percentage of residual plant counts remaining after the three and five-year periods.
Initially, the trial was established at a dryland sowing rate of four kilograms per hectare, resulting in an average starting plant count of 37 plants per metre square, which suited our target of 30 – 40 plants per metre square based on our average annual 420 millimetres rainfall.
The results shown in the graph on this page now indicate the updated results after five years of the trial period, which have shown some significant differences in the performance of varieties, and quite a variation in the results that were seen after the three year period was measured. In particular, some of the Highly Winter Active material has distinctly dropped off in the recent two years.
By conducting extensive grazing trials and closely analysing the results, S&W Seed Company remains dedicated to delivering superior lucerne varieties with exceptional grazing tolerance. Our commitment to rigorous testing and ongoing improvement ensures that farmers can rely on S&W products for optimal performance in grazing conditions.