• Improving grassland productivity: from the soil below to the sward on top!

To maximise the performance from grassland it was important to take a ‘bottom up’ approach: to ensure soil structure was in good condition, to tailor fertiliser applications to cost-effectively correct nutrient shortfalls, to reseed regularly to maintain good yields and quality, and to keep swards clean with targeted weed control programmes.

These were just some of the recommendations for livestock farmers who attended a series of evening talks by the Grassright Group. The events were hosted by Spunhill Farm Sales, and took place in Wales, at Brook House Mill in Denbigh, and in Shropshire at Spunhill’s Ellesmere headquarters and the Salwey Arms near Ludlow.

The Grassright Group is a collaboration between three companies – OPICO, GrowHow and Limagrain UK. Amongst the Group’s activities is the provision of technical and practical advice to farmers on maximising grassland productivity.

OPICO’s Nick Rider told farmers that soils were vulnerable and easily damaged by heavy rain or flooding, by grazing animals in wet conditions, and by machinery traffic.

Research had demonstrated reductions in first cut silage yields of up to 30% could occur as a consequence.

Compaction could be assessed using a spade and digging a number of holes in a field, and examining the soil profile. Where compaction was up to 250mm deep, then this was best resolved by subsoiling with a Sward-lifter. He recommended the spacing between the subsoiler legs should be 90cm, to prevent slumping after the ground had been worked.

For shallower compaction, as caused by livestock, then an aerator or slitter should be used. To break up surface compaction, then grass harrows did a much more effective job than chain-harrows.

Limagrain’s Brian Copestake outlined the yield and quality advantages that newer leys had over old leys. He showed data in which a one-year old ley produced 14t/ha of Dry Matter with a Metabolisable Energy content of 11.5 MJ/kg DM. By the time that ley was 8years old it would have suffered ingress of weed grass species and declined in quality, palatability and yield. Research showed is would only be yielding 6.7 t/ha DM, at 10.3 MJ/kg DM. The difference in energy yield was 95,000 MJ/ha, equivalent to the energy in 7t of wheat.

Mr Copestake also recommended that farmers avoid sowing dual-purpose grass mixtures, as these were always a compromise. Instead, if a given field was predominantly going to be grazed, then a grazing mixture, such as Maxigraze with white clover, was a good choice as it includes ryegrass varieties selected so the sward remains seed-head free for a long period.

Agronomists from Spunhill – Rhys Owen and Bryn Thomas – told farmers that a targeted approach was needed to control weeds effectively. The timing of spray applications was very important for success: weeds always needed to be actively growing. More specifically, docks needed to be at the rosette stage, and buttercups needed to be sprayed before they flowered.

Good practice was essential when handling agrochemicals: a single cap foil from a pesticide container could contaminate a 1m wide stream for 30km.

Farmers were also reminded that from November 2015 all sprater operators must hold a recognised certificate, and the loophole of ‘Grandfather rights’would cease.

GrowHow’s Elaine Jewkeswarned farmers that phosphorous may be less available to crops in early spring as waterlogged soils take longer to warm up, and phosphorous is less available in cold soils. It can also be lost in the run-off after flooding.

She recommended that farmers have a comprehensive soil testing programme in place to ensure correct pH and nutrient balance – N, P, K and S – to support grass growth without spending money on unnecessary fertilisers. For instance, farmers who just applied a standard 25:5:5 fertiliser in the spring when only nitrogen and sulphur top-ups were required, couldinstead save around £13/acre by choosing Growhow’s Single Top fertiliser and still get the desired yield and quality of grass.

With maximising production from home-grown forage a key focus of the meeting, Miss Jewkes also presented information on GrowHow’s new N-Min service for maize fields. It predicted the nitrogen in the soil that would become available over the season. Trials had shown this to be more accurate than the RB209 recommendations.

More information on best practice grassland management can be found at www.grassright.co.uk. Farmers interested in obtaining a sprayer certificate can contact Spunhill on 01691 626000 for information on training courses.