Autumn closing on sheep farms
While we are still only in October grassland management at the moment and over the coming weeks on farms will have a major impact on the start of 2021 grazing season. Sheep specialist Ciaran Lynch and researcher Philip Creighton give some advice on grazing out paddocks and when to close.
There are a number of factors that will influence spring grass availability such as the weather over the coming months. However there are a number of the key determents of grass availability and sward quality that are within the farmer’s control. These are the post grazing residual, when you close the paddock and the closing cover on the farm. Correct management and closing of paddocks from now onwards will set them up for grazing next spring and get the season off to a good start.
Grazing out paddocks
Let’s deal with the grazing residual first, our aim here is to remove any dead material at the base of the sward particularly in heavy covers and have a fresh re-growth over the winter. Aim to graze down to 3.5 to 4cm to graze out paddocks fully. There is a balance here between meeting daily feed requirements and achieving adequate graze outs. Aim to reduce the grazing area or increase the grazing group size to achieve faster graze out. This in turn will reduce the amount of time ewes or lambs spend at grazing lower covers. Splitting paddocks with temporary fencing works particularly well when trying to clean out heavier covers.
When, where and how much to close up?
Aim to allow paddocks a 120 day rest period over the winter months prior to grazing next spring. To achieve this we need to start closing paddocks from mid to late October onward. This is to allow covers to build on those first paddocks when growth is still active. During late November into December and January grass growth will be minimal. The higher opening covers next spring on these earlier closed paddocks will allow them to respond faster to improvements in temperature and fertilizer application. Most farms need to aim for a closing farm cover in December of 600 kg/DM/Ha. Work undertaken in Athenry and on commercial farms has led to the development of a simple template outlined below that provides a guide to when and how much ground to close up during the coming weeks.
Autumn closing targets
|Date||% Area Closed||+ 120 Days|
|Late October||20||Early March|
|Mid November||40||Mid March|
|Late November||60||Late March|
|Mid December||80||Early April|
This is based on early March lambing flocks. Later lambing flocks may delay slightly but it’s essential that the first 20% and 40% are closed at the suggested times outlined above. This is to allow sufficient regrowth as these first closed paddocks are vital to a good start next spring. Aim to close paddocks that will be used first at turnout, generally the more sheltered ones near the yard. From there close the rest in the same rotation that you intend to graze them in next spring.
The golden rule for the coming weeks - avoid re-grazing closed paddocks!. This may be a tempting prospect on many farms to delay housing; however it will come at a cost. Let’s put this in context, currently a ewe requires 1.6 kg/DM/day grass whereas as at turnout next spring the requirement will be 50% higher, increasing more each week in early lactation. Therefore in situations where grass supply is limited it will be easier and less expensive to meet the ewes feed requirements during mid-pregnancy than next spring during lactation.