How to improve feed quality and save money by maximising the potential of grazing grass

Scottish dairy farms can grow quality grass – and lots of it – as one Stirlingshire unit has discovered while taking part in AHDB’s Forage for Knowledge programme*. Robin Young’s Waterside Farm at Kinbuck outside Dunblane is improving feed quality and saving money by making more of grazed grass.

Being able to grow 12 MJ/kg DM ME quality grass throughout the grazing season has surprised Stirlingshire dairy farmer Robin Young. But measuring and testing grazed grass every week for the past seven years, as part of AHDB’s Forage for Knowledge programme, has shown him that Waterside Farm is capable of producing quality, plus 12 t DM/ha from its grazing paddocks.

Furthermore, a network of tracks installed seven years ago, when Mr Young switched to rotational paddock grazing, means that cows can access grass even on the wettest days, while minimising poaching. Turnout is now four weeks earlier in spring, with cows also staying out two weeks later in autumn, saving silage and labour, as well as slurry handling and bedding. “I grow more grass than I ever thought I could”, he confirms. “We have shortened winter housing, and spring turnout is now in March (March 19 this year), not the traditional 20 April. We started plate metering in 2013 and joined AHDB’s Forage for Knowledge as a benchmark to start with, and it grew from that. It made sure we understood how the grass plant grows and how quickly.”

Mr Young runs a 180-cow crossbred herd, block calving in autumn, plus 107 followers, on his all-grass farm covering 102 ha. Soils are fairly light and free-draining and get an annual rainfall of 1,000–1,100 mm (40–44”). A further 15 ha are rented for youngstock grazing. The average yield is 7,000 l with 3,700 l from forage and 1.5 t cake/cow. The cows have a grazing platform of 56 ha divided up into 28 paddocks. By grazing ryegrass in rotation, moving to a fresh paddock every day, it is kept leafy and vegetative, which prevents it from getting stemmy and running to seed. It is this leafy grass that is 12 ME and highly palatable, so cows will graze it down.

“Grass is pretty consistent through the season, and you can’t afford to buy a cake of that quality spec: 12–13 ME and way into the twenties for crude protein % (it was 27.5% this spring). I always thought August grass was inferior, but when you graze it tight and grow it to 2,800 kg DM/ha, it is still much the same quality, so you get spring grass all year round”, says Mr Young.

Data from Scottish dairy farms shows that well-managed grass yields 15.3–17.9 t DM/ha/year. Individual paddocks on Waterside’s platform produce 11.5–13.0 t DM/ha, with growth rates of 100–120 kg DM/ha/day in June. Compared with the national average, Mr Young feels he probably needs to do more reseeding to see what a difference it would make, having concentrated so far on renewing old permanent pasture. He makes 1,200–1,300 t of silage each year, which is unchanged from when the herd had just 120 cows, reflecting the greater intakes of grazed grass.

One change that didn’t work for Mr Young was growing standing hay as a fibrous feed for dry cows. This is usually done by shutting up a paddock in June and allowing it to go to seed, then strip grazing it from July onwards. Changing weather patterns produced a wet summer four years in five and simply created a mess. “It gets horrible in the bottom, and we end up poaching. Last year we switched to a transition nut with chopped straw and silage and housed cows 10 days pre-calving. They were easier to manage, and it helped improve fertility.”

Weekly grass measurements with a plate meter are used in a grazing software package to work out how much grass is available ahead of the cows. This helps to allocate grazing area on a daily basis, decide whether there is a surplus that needs to be made into silage, or realise that a deficit is looming and concentrates, or silage needs to be fed. Measuring and managing are carried out by Mr Young’s contract managers, Pat and Jess Kimpton, who are coming to the end of their five-year contract farming agreement.

They learned their grassland management skills in Waikato, New Zealand, working with 950 cows on 240 ha. Alongside the regular perennial ryegrass and clover mixes, there were swards of plantain and chicory to cope with the three-month summer drought. “I learnt how to measure and create a grazing wedge on the platform. How to adjust stocking rates, manage my surplus and deficit through the year, as well as when and how much to supplement cows”, says Mr Kimpton. “But the skill of management is to adapt it to any grazing platform and learn to grow and manage grass to build a wedge and feed the herd according to a farm’s soil type and weather pattern. Measuring gives you the confidence to make decisions.”

His challenges in Scotland included adapting to rain in August as once it turned wet, it stayed wet, hence the unsuccessful standing hay. Grass management in the late season has also been tricky as it is very weather dependent. There has to be a balance between grazing down efficiently and leaving enough quality behind to carry grass over to spring, he explains. “Management at the shoulders of the season is crucial to success as this is where the gains are to be made. It’s about when to turn cows out and how long to let fresh calvers graze before housing. We can keep the quality in autumn, it’s just harder to get intakes as they need enough time to eat it and not just trample grass.”

While the herd moves paddocks on a daily basis to avoid poaching, undulating fields don’t help, says Mr Kimpton: “You have to be careful with ground conditions as cows can penetrate and damage soil structure when walking to graze. But we have a good infrastructure and have spruced up tracks with a topping of Astroturf which reduced lameness, at shoulders of the season, due to stones which caused sole bruising.”

Because cows can get anywhere on a track, Mr Kimpton has been able to bring silage ground into the grazing rotation when needed. Protecting regrowth has improved grass utilisation and added another 500 l onto the herd average, bringing it up from 6,500 l without increasing cake usage: “We create alleyways to get to graze silage ground after the third cut and protect regrowth with back fencing”, he adds.

For Mr Young, looking to start his next calving season, grazing management will continue to develop with a new contract manager. “We have measured and benchmarked and learned a lot. You wouldn’t feed a TMR without knowing its nutritional content, so that’s why analysing grazed grass works. We were paddock grazing here 50 years ago; the difference now is that we have the tools to measure it and the software – and we didn’t know about dry matter intakes then”, he says.