Live by the sward: mixing it up can save you money and help the environment

There is a big push on in the Department of Agriculture to map out a 10-year plan to prevent the agriculture sector becoming an environmental pariah. The Ag-climatise report received hundreds of submissions on how farmers should implement a minimum of a 10pc reduction in carbon emissions over the coming decade.

The feedback is that there is an over-reliance in the sector on protected urea being the magic bullet that will save everyone’s skin.

Instead, the Department wants to see more emphasis on measures to reduce the amount of nitrogen being applied.

That all sounds very sensible, but it flies in the face of what farmers have experienced in recent years.

The dairy partnership I’m involved in is one example. It’s part of a discussion group that went on a skite to South Africa about four years ago not the first place Irish farmers might look to for cuttingedge thinking on grazing technology

and several members came back from that trip pumped up about the concept of a multi-species sward.

Similar work had already started in UCD’s Lyons research farm, looking at the benefits of seed combinations that included the usual suspects like perennial ryegrass (PRG) and clover, but also more oddball species like chicory and plantain, and traditional grasses like Timothy and cocksfoot.

I remember in ag college being lectured about the importance of eliminating low-production grasses like those two latter ones in favour of PRG.

That was back in the days when the easiest way to increase profit was to maximise the amount of grass drymatter (DM) per hectare by chucking lots of nitrogen on PRG monoculture swards.

But the PRG monoculture model has passed its sell-by date.

Now the goal is to maintain production, but with far less nitrogen inputs. A clover-rich sward can achieve some of this, but it’s weaknesses include the increased risk of bloat, delayed growth and its lack of persistence.

Better to increase that mix threefold to include the likes of herbs like plantain and chicory, which pull up a broader range of minerals from deeper-rooting profiles than PRG or clover.

Drought-tolerant

This means that the sward is more drought-tolerant, which is likely to become a more important feature as our seasons get more extreme.

It also works the other way, in that the deeper-rooting profile also helps percolation.

In addition, chicory was always included in old pasture mixes due to it’s anthelmintic effects, and there are some indications that plantain can reduce nitrous oxide emissions when included in the diet.

The Timothy grass works well on heavy soils and helps fill the gaps, as well as covering early and late growth periods, which flattens the production curve that characterises PRG.

The best grass managers are beginning to reassess the costbenefits of having to save all those grass surpluses that PRG creates in June and July compared to a sward that produces at a more consistent level throughout the grazing season.

Red clover is often also included with white to vary the rooting profile and provide cover for the white clover, which can often take a year or two to establish.

In the last three years members of our discussion group have reseeded 10-15pc of their milking platforms with this type of mix.

It requires a bit more management, since it can be trickier to establish than a PRG monoculture, and it costs about €50 per acre more in seed.

But the benefits are clear. Fertiliser use can be cut by as much as 70pc without affecting DM yields.

This massive drop in fertiliser use is not only good news for your pocket and carbon footprint. Your soils also appreciate it, with earthworm counts increasing, which helps improve the soil’s ability to resist poaching.

Over ground, the bugs are happier too, with increased biodiversity of plant structures encouraging more insect activity.

Change of focus:

The inclusion of traditional grasses such as Timothy in a multi-species sward can reduce fertiliser bills without affecting yields

What’s not to like? Yes, it takes more management, and no we aren’t going to cover the entire area with a multi-species sward yet. But we are steadily increasing the area each year as the confidence in the system grows.

Why haven’t you heard more about this before now?

Possibly because agri-business isn’t particularly interested in promoting technology that could reduce fertiliser, dosing and mineral lick sales.

Also because the Department rejected a proposal to roll out trials for this across farms using for European Innovation Funding.

It was a missed opportunity that Teagasc Johnstown, Moorepark and UCD Lyons have been trying to make up ever since.

Agri-business isn’t too interested in promoting technology that could reduce fertiliser and dosing sales