The Teagasc Heavy Soils Programme was set up in 2010 with the main aim of improving the profitability of grassland farms on heavy soils. Programme coordinator James O’Loughlin says that farmers on heavy soils have to be excellent grassland managers because they have so many more issues to contend with compared with a farmer on dry ground.

The programme helps farmers to adopt key technologies, including appropriate drainage solutions, high-quality pasture management, land improvement strategies and efficient herd management.

According to James, this spring has been extremely difficult for farmers in the programme. “It’s only in the past week grazing has really commenced on the farms. With the exceptionally high rainfall, land was not suitable for grazing even where drainage work was carried out. Some farms got cows out to grass in February, but this was far lower than we would like,” he explains. “The benefit of draining land for most farms is when dry weather does come, the land is ready to graze quicker compared with heavy, undrained ground,” says James.

The aim of the programme is to improve profitability and this can be achieved when the infrastructure is in place on the farms to grow grass. The Irish Farmers Journal spoke to Danny Bermingham from Doonbeg, Co Clare, who has participated in the Heavy Soils Programme since 2010. Danny shared some of the challenges he has faced and the work he has carried out to improve productivity on his farm.

Danny started grazing by day last week. The wet winter, followed by a very wet spring, meant grazing has been impossible up to now.

“The ground is very cold now and it’s not surprising given that it has been raining every day for the past four months, more or less,” says Danny. He has let his mainly New Zealand Friesian-bred cows (550kg liveweight) out grazing by day since 15 March, corresponding with the improvement in weather conditions and, at night, they are fed silage inside.

“Cows are milking well currently and are producing 29 litres, but they are getting 6.5kg concentrates in the parlour,” explains Danny.

Last January, there was a cover of 850kg DM/ha on the farm and this has reduced to 600kg DM/ha. “The grass has melted away because it hasn’t been grazed; there is a yellow butt in places that needs to go. A river runs through my land and anywhere it burst its banks and flooded paddocks, there is no grass left. Leather jackets are also a problem now, they eat the grass roots which doesn’t help growth at all. I will spray them with an insecticide this week, but I’m afraid the damage is already done,” he said.

Danny started spreading three bags per acre of Optigrass fertiliser (a NPK plus sulphur, sodium and magnesium mix) on the land, but says it is the latest he has ever spread fertiliser. “We would usually have fertiliser out on paddocks by the beginning of March at least, but the ground just hasn’t been trafficable. Watery slurry is going out on paddocks after grazing now,” he said. The cows out grazing by day now are not doing any damage according to Danny and he is optimistic about letting them out full-time from now on. “On very heavy ground, it is far more difficult to follow the spring rotation planner. Wet land is far less dependable. We try to get cows out grazing whenever we can but this year it has been far more difficult. To date, only 2% of the land is grazed,” Danny says. The cows out grazing now are on previously drained ground, but there is more work to be done, with paddocks not drained still unsuitable for grazing and they will need more dry days.

Land drainage

A considerable investment has been made in terms of land drainage on Danny’s farm and he believes it has been worth it. “Since we joined the Heavy Soils Programme, approximately nine acres have been drained using the Teagasc method at a cost of €2,500/acre,” he says.

For anyone planning on investing in land drainage, Danny warns it is not for the faint-hearted. He assures, however, that the investment is paying dividends and, last year, he could see the difference between a well-drained reseeded paddock and paddocks that had no work done.

“On average, we grew 10t DM/ha on the grazing block (Figure 1). Our poorest performing paddocks that had no drainage work only grew 5t DM/ha and our best paddocks grew 16t DM/ha,” he says.

The drainage method that has worked best on Danny’s farm was deep drainage. This involved digging 1m-deep drains the length of paddocks, spacing them 15m apart. Four-inch JFC smooth, interior-perforated, plastic drainage pipe was put down at the bottom of these drains and they were filled with drainage stone to the top of the subsoil. Top soil was placed over these drains. Next, a mole plough was used to make a series of drainage channels running at right angles to the main collector drains at a depth of 24in.

The bullet-shaped drains left by the mole plough allow a speedy water flow from the field into the collector drains. The collector drains feed into deep, open drains at the perimeter of the paddock.

Danny says the key to this method working well is having the open drains deep enough to allow the collector drains to work properly. “Don’t have the outlets of the collector drains on the floor of the main drain. Allow some room for silt buildup,” he explains. In the past, tile drains were used in some paddocks but Danny said they did not last.

The drains consisted of 1ft to 1.5ft deep drains filled to the top with drainage stone without any drainage pipe. “With no drainage pipe, they eventually silted up and got blocked,” he says. The drains that were put in place following Teagasc advice have worked very well, but Danny knows that it is not a case of putting in the drains and that’s it – they need maintenance.

“The main drains have to be cleaned out regularly to keep the depth and the mole drainage has to be monitored because the moles will break down eventually. That said, once the main collector drains are in place, the main investment is made,” says Danny.

When Danny started farming, he had to make considerable investments in housing and slurry storage because cows were inside for six months of the year.

Now, with that investment made, he plans to continue investing in land drainage and paddock infrastructure as far as income allows into the future. Danny says that farming on heavy ground is tough, but with the right techniques it is possible to be profitable. This year, with poor milk prices, big drainage work is unlikely but soil fertility and drainage maintenance will continue.

  • This spring has been very difficult with grazing only starting now.
  • Land drainage is a long-term investment but worthwhile when done correctly.
  • Drainage work needs to be maintained.
  • Heavy farms need good slurry storage and housing facilities because winters are longer than drier farms.
  • Drained and reseeded land on Danny’s farm grew over three times as much grass as paddocks with no work done in 2015.
  • To read the full Reseeding Focus Supplement click here.