Johnstown Castle Update - 29-11-22
Aidan Lawless
Grass clover v Multi species swards 2022 performance
As 2022 comes to a close we now have 3 full years comparison with a grass-clover (GC) versus multi-species swards (MSS). These two, small sized farm systems were set up in 2019 with the establishment of a six variety multi species mix (two grasses, white clover, red clover, chicory & plantain), alongside a standard grass/clover mix.
Cow Performance
Cow health & performance across both systems for the 3 year period has been excellent, what is striking is how evenly matched both groups have been in terms of milk solids production across all 3 years to date. 2022 has seen an increase of ~ 20kgs/MS/cow but this came at a cost (see table 1). Our concentrates fed per cow will go close to 1100kgs for the year, this is well above our target of ~700kgs and is a consequence of very poor growth rates for most of July/August due to moisture deficits. We were lucky in that we got some rain over this two month period (~50mm in total), which was enough to prevent swards from “burning up”, but growth rates were generally running around 20kgs/day compared to an expected 50-60kgs.
Sward performance
Both systems were impacted by the drought, but the MSS swards did survive a couple of weeks longer before silage supplementation was required. Overall both systems grew ~12.5 T DM/ha which would be 2 T DM/ha below our target. For the previous two years the MSS swards were coming in ~1 T DM/ha less than GC, this year the MSS grew slightly more than GC whilst receiving 90kg N/Ha less artificial N (144 v 54). It would appear the summer drought had less of an impact on the MSS system.
Growth rates from mid-Sept to mid-Nov have been excellent, unfortunately the very wet weather for the past 3 weeks has impacted our ability to maximise this late growth, we’ll be carrying higher covers into 2023 on both systems than previous years as a result, possibly as high as 1000kgs DM/ha on the GC system, with the MSS herd closer to 900kg DM/ha, heaviest covers will be around 1600-1700 Kg DM/ha, with a flatter wedge than might be expected due to the excellent recovery on the paddocks grazed in last 4 weeks.
How both these systems perform over the next three years will be really interesting, the composition of the swards is changing over time, with a noticeable reduction in chicory on the MSS, much more work is required to determine the best management practices for a long-term sustainable MSS system, but results to date are promising.
Table 1. Highlights the performance of both systems to date in 2022