Welsh Government

11 November 2021


Written by Rhys Williams, Precision Grazing Ltd


Preparation for spring is well under way at many grassland farms in Wales. Escalating concentrate feed and fertiliser prices means that ensuring a good supply of grass in early spring will have more of an impact than ever on managing costs and improving the financial bottom line on all grassland farms. 

There are multiple benefits of opening the grazing season with a healthy average farm pasture cover. These benefits include:

  • Access to very high-quality feed (ME>11 and Protein>20) at a time of year when livestock requirements are at its highest, which potentially eliminates the need for purchased feed.
  • Maximising the impact of the ‘grass grows grass’ principle, which means that the more leaf area that is available to capture sunlight in spring, the more it will grow; this reduces the need for fertiliser input.
  • Grazing grass saved over winter in early spring kickstarts the plants’ growing season – which again reduces the dependency on applied fertiliser.
  • Access to grass in early spring also allows the opportunity to turn out stock early. This would reduce housing and other winter-related costs, and helps housed livestock to transition on to pasture early.


Closing rotation 

Planning for spring on beef and sheep farms should start in late summer. Grass covers should be built in preparation for the closing rotation; this is the final grazing of the year, which will set up the following grazing season. The closing rotation should be planned in a way that allows a sufficient winter rest period and grazes the pasture well, cleaning out dead material to ensure that the grass present in spring will be leafy and of high quality.

Timing the closing rotation is dictated by the winter rest period of the farm. This mainly depends on the farm climate, soil fertility and pasture composition. On average, farmers in Wales should aim for a 120-day rest period; this means that fields grazed in early November need to be rested until early March.

Livestock should be mobbed up into the smallest number of groups that the system allows and rotated around the farm. The order in which the fields are grazed in the final rotation is the same order in which they will be grazed in the opening rotation in spring. This means that fields grazed at the end of the closing rotation in December would not be grazed until April.

Good clean grazing is best achieved by short grazing on-time. The period in which livestock graze an area during the closing rotation should be restricted to no more than four days. The shorter the on-time, the cleaner grazing and the higher the utilisation.

Farmers have several options to provide the winter rest period that include forage crops, housing, sacrifice areas and off-farm grazing – each having their pros and cons. Each farmer will need to decide which option best suits their farm and system.


Improving grass utilisation is a priority at Farming Connect demonstration sheep farm, Pendre, Llanfihangel-y-Creuddyn, near Aberystwyth. Farmer Tom Evans has seen significant gains from implementing a rotational grazing system on his 19ha home block. Working closely with Precision Grazing Ltd, Tom has plans in place to set up another successful grass-growing season. 

The sale of the majority of fat lambs and the transfer of some ewes to another block mean that Pendre has 190 lowland ewes and 90 fattening lambs on farm in early November. All fattening lambs will have left the grazing area before the end of November (either slaughtered or sent to be fattened elsewhere), leaving only the ewes grazing during December.

Lambing starts indoors at Pendre in mid-February. Ewes are therefore now in the early stages of pregnancy. Ewes at Pendre weigh on average 70kg and therefore at 2% of body weight; their daily requirements are 1.4kg DM/day of grass and the total group demand is 266kg DM/day.

Tom regularly measures grass pasture covers at Pendre as part of the Farming Connect Welsh Pasture Project. Average farm pasture cover at the beginning of November on the 19ha block was 1950kg DM/ha. The area for the closing rotation is reduced to 16ha, due to 2ha being allocated to the fattening lambs until the end of November; another 2ha have already been shut to turn ewes and lambs into post-lambing in mid-February. 

For good clean grazing, it is recommended that pastures are grazed down to residuals of 1400kg DM/ha on the closing rotation. It is estimated that the utilisation of the pasture available is 80% (this varies with ground and weather conditions). Given the above information, and an average farm cover of 1950kg DM/ha, there is 7200kg DM of pasture available – which, divided by the group demand, is the equivalent to 27 days of feed. 

Ewes and newly-born lambs turned out in mid-February will be given three weeks to settle and strengthen before being mobbed up to start the opening rotation in early March. The climate, soil fertility and pasture composition at Pendre allows for some winter grass growth; therefore, the winter rest period at Pendre can be reduced to 110 days. To provide sufficient rest period until the beginning of March, the final rotation should therefore start on 10 November. Given the 27 days of grass feed available, the ewes will need to come off the grazing platform during the second week of December. Pendre boasts excellent sheep housing facilities; as a result, Tom’s preferred choice for accommodating the ewes until the start of the grazing season is to house and feed silage at maintenance level; concentrate feed will be introduced to multiple-bearing ewes as lambing approaches.

The map below shows how Tom has subdivided Pendre to accommodate the rotational grazing system. The 15ha available for the closing rotation have been subdivided into 17 grazing areas that will provide the group of 190 ewes with on average a little over a day and a half grazing in each area.

Figure 1: Map of Pendre Farm, showing grazing rotation


Key Message: It has been an excellent year for beef and lamb produce prices, which has diluted the impact of costs on profitability. However, the strong market can potentially lead to a false sense of security. The price of produce is largely out of the farmers’ control, and can potentially fall as quickly as it has risen. Costs have also inflated, and are less likely to fall than the price of farm produce. Measures should be taken to manage costs closely; improved grass utilisation should be a part of this process.

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