Top-quality grass silage and robot milking are driving cow performance at a Pembrokeshire dairy farm. Debbie James reports.
Harvesting grass more frequently and targeting an earlier first cut is allowing the Williams family to make better quality forage to offset purchased feed costs.
In 2020, the quality of the first and second cuts averaged 12.7 ME, with protein hitting 13.5%.
“Good quality silage is a key component in our herd’s diet. It forms the base upon which we build a highly palatable, nutritious and inviting ration for our cows,” says Michael Williams, who farms with his parents, Gareth and Annette, at Fagwrfran East, Puncheston.
Michael says: “By taking first cut earlier and making more cuts of silage, we achieve better silage quality throughout the year, which is important as grass silage makes up most of the diet throughout the year, even when milking cows are out at pasture in summer.”
The dairy enterprise revolves around an all-year-round calving herd of 145 mainly Holstein cows with some Jersey and Norwegian Red cross-breds.
Emphasis is on producing consistent yields with good constituents to suit the farm’s supply contract with First Milk.
The system had been based around twice-a-day milking in a 10:20 swingover parlour, but when that needed upgrading, different options were explored.
Michael says: “I wanted to ease the workload on my parents, but we did not have sufficient cow numbers to justify the salary of a full-time worker.”
And with a young family of his own, milking twice-a-day every day was not an appealing prospect.
He says: “We started looking into robotics and figured that the best route was automated milking.”
There are three robots in a purpose-built dairy complex which includes cubicle stalls for 170 cows.
The herd was initially fully housed, but last summer cows were given access to pasture.
Michael says: “The decision to graze was made because we wanted to support our milk buyer’s efforts to market our milk. It made sense to allow cows the freedom to choose to access pasture.”
Cows can pass through a smart gate during the day once they have been milked.
“They can wander back to the building for feed or shelter whenever they wish,” says Michael.
He plans to extend the pasture access time this year.
However, feeding priority remains a good quality total mixed ration (TMR) of grass silage and maize, with 18 hectares (45 acres) of maize grown which can be challenging at an altitude of 600ft above sea level, Michael says.
Grass quality is a key driver for making good silage, with the true benefits of the multi-cut system in ensuring leys are in good order.
Preparations begin as early as autumn, when about 300 tack sheep are turned in to both grazing and silage fields to clean up residuals from mid-October. They remain on the farm until the beginning of January.
Young fresh grasses perform much better and respond well to any inputs than older leys, so the target is to reseed 6-8ha (15-20 acres) annually, depending on weather and stocking rates.
The preference is to reseed with perennial or hybrid ryegrass in late August or early September to give fresh grass a chance to establish before winter.
A zero-tillage single-pass machine is used. “This is great for our hilly farm, especially fields we know are stony,” says Michael.
“It also makes reseeding much more economical and less vulnerable to weather.”
First applications of fertiliser are made as soon as fields can be travelled without marking, usually in late March, but in early April for some areas of the farm.
The first application in preparation for first cut is 75kg of nitrogen (N)/ha (30kg N/acre), followed by 50-55kg N/ha (20-22kg N/acre) immediately after each subsequent cut.
Michael says: “We try to use a fertiliser which includes sulphur; this is essential for healthy plant growth.”
Soils are sampled every three or four years. P and K indices are mostly three, but some are at four.
Most fields only receive N fertilisers with most of the P and K coming from manure produced on-farm, but some fields receive targeted P and K applications depending on soil sample results.
Great emphasis is placed on utilising stored manure.
Michael says: “We try to treat slurry as a nutrient source rather than a waste product, applying early in spring and after each cut of silage.
“We handle slurry ourselves using an umbilical system and tanker to further outlying fields.
“One of the many benefits of the multi-cut system is the ability to apply slurry little and often to growing crops.”
The first cut is taken around May 12, with subsequent harvesting carried out at intervals of 33-35 days. A silage additive is used.
All the mowing and tedding is done in-house and a contractor chops and ensiles it.
Michael says: “We aim to mow as much as possible in the afternoon and will ted immediately, aiming to allow grass to wilt for 24 hours before the forager arrives.”
About 59ha (145 acres) is harvested for first cut, 40ha (100 acres) for the second and third cut, and 30ha (75 acres) for the fourth. A total tonnage of 1,995 tonnes is ensiled.
Some second and third cuts are left to mature a little longer to make bale silage to feed to youngstock, dry cows and beef cattle. All beef calves are retained and reared on a simple grass-based mob grazing system with baled silage fed during winter.
These are usually sold as store cattle at 18 months, but due to TB restrictions they are being finished on-farm this winter. Good clamp management pays dividends in preventing silage spoilage at ensiling and feeding out.
The clamp must be clean and side sheets are used, with enough spare to fold over to overlap the opposite side.
A single top sheet is used between cuts and, once the clamp is filled and sealed for the final time, it is covered with an oxygen barrier and top sheet.
These are covered with a combination of secure covers and silage mats.
Michael says: “We like to layer the crop as it is coming in so that during feeding out, field variations are evenly distributed through the clamp.
“We always try to have two machines on the clamp during filling, one pushing in and the other constantly compacting.”
Michael, a member of North Pembrokeshire Grassland Society, won the 2020 Federation of Welsh Grassland Societies’ All-Wales Silage Award for clamp silage.
What does he think is the single most important factor to bear in mind to make quality silage?
“It is impossible to pick one thing, but the weather before and during silage-making is vital,” Michael says.
Attention to detail at mowing and tedding and preventing contamination combined with excellent pit management, plenty of compaction and ensuring the pit is covered adequately are important too, he adds.
“I suppose attention to detail at every stage makes for the best outcome,” he says.