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From mid-March to mid-April, there will be a growing number of livestock farmers filtering cattle out to grass where ground conditions permit and there is adequate grazing available.
Turning cattle out in early spring, and keeping grass in front of stock, takes high levels of management and a degree of planning.
It is not for everyone and there will be farmers who have tried grazing in March, but have had a bad experience and are reluctant to try again.
But where good planning is in place, there are multiple benefits to be gained from an early turnout.
These include compensatory growth in cattle stored over winter, a reduced workload in terms of indoor feeding and bedding, as well as lower feeding costs.
If there are plans to turn cattle out to grass over the next month, outlined are some tips to keep animals grazing.
1 Walking the farm every week
Before turning cattle out, it is important to walk the farm at least once. But ideally, the farm would be walked on two consecutive weeks before turnout.
When walking the farm, note ground conditions and take a measurement of grass covers present, either with a plate meter, sward stick or with a couple of height indicators marked on a boot.
Identify how many fields can take cattle and try to plan out a rotation for moving animals once the first paddocks are grazed off.
Continue to walk the farm weekly, measuring the change in grass covers and ground conditions, as well as identifying which paddocks need fertiliser.
Use this information to determine if more cattle can be slipped out to grass, or to hold off in case those animals already grazing are likely to run out of grass.
2 How long should the first rotation last?
Grass growth should slowly increase over the coming weeks, but it will probably struggle to meet livestock demand until late April, if not May.
As such, there is a risk cattle will run out of grass if too many animals are turned out too soon. This is why walking the farm weekly is important.
Having a bank of grass built up over winter will help keep cattle grazing until growth rates exceed demand.
If the aim is to turn cattle out in mid-March, then realistically, you will need around 30 to 35 days of grass ahead of stock in the first rotation. For an early to mid-April turnout, around 20 days of grazing days ahead are needed.
Of course, it is possible feed silage and meals to grazing animals in order to slow down the rotation and stretch out covers.
But there is a risk of poaching with this option. Swards that are heavily damaged in spring will take time to recover.
3 Grass budgeting
To work out how many grazing days are in front of cattle, do a few basic grass budgets. For a beginner, the aim is to graze swards down to a residual height of 4cm (1,600kg DM/ha), which is roughly the height of the toe cap on a boot.
Roughly speaking, every 1cm in grass height above 4cm is 250kg DM/ha of grass available for grazing.
Dense swards with a tight-knit base will be closer to 300kg DM/ha, open swards will be closer to 200kg DM/ha for every 1cm in grass height.
Taking a field of 5ac (2ha) in size, with an average sward height of 7cm in March, there is a cover of 2,350kg DM/ha, giving 750kg DM/ha of available grass for grazing.
Cattle will eat around 2.5% of their bodyweight in dry matter every day. For a group of 10 heifers weighing 400kg, they will consume 100kg DM/day.
Therefore, the 5ac field will last the 10 heifers around one week, assuming ground conditions are relatively good.
On this basis, it would take 20 acres to carry this group on a 30-day rotation in early spring, unless grass growth starts to ramp up significantly.
4 Turning cattle out hungry in the morning
Restrict silage intakes so cattle go to grass hungry. This should help animals settle quicker and start grazing, inflicting less ground damage.
Target early to late morning for turnout. This gives cattle time to adjust to the change in temperature after leaving the shed.
There is still a risk of cold weather and frost in the weeks ahead, therefore turning cattle out in late afternoon when temperatures are falling increases the risk of pneumonia.
5 Tidy up horns and other management tasks
Make a point of tidying up any missed horns, as well as any male cattle that missed out on castration. Sort out any problems with feet also.
Ensure any vaccines and booster shots are up to date. Also, check all cattle have two ear tags leaving the shed.
6 Choosing fields with some shelter
As there is a risk of cold weather in March and April, where possible, choose paddocks with shelter for weanlings and cows with young calves. If these paddocks are close to a handling unit, even better, in the event of a pneumonia problem.
7 Grazing silage ground
If cattle go out in March, target silage fields first. Chances are these are drier fields and therefore, more suitable to carrying stock.
Grazing off grass and dead matter that accumulated on over winter will improve silage quality in the first cut. Grazing will also stimulate grass to start growing.
Provided stock are removed from silage ground by early April, there will be no reduction in grass yields when harvesting the first cut. If cattle are left on silage ground too long, yields will be reduced.
8 Hold off on temporary electric wires
Hold off setting up temporary electric fencing wires and posts until cattle have settled at grass. As soon as cattle hit grass, they will take off running.
More often than not, they will break through polythene wires set up as a temporary fence to split a paddock. Allow cattle to settle into grazing, then erect a temporary wire later the same day.
9 Fertiliser
Plan out fertiliser applications now. Where grass covers are low, and a paddock is unlikely to be grazed until the end of the first rotation, spreading 2,000 gal/acre of slurry will boost growth rate.
Where covers are good and paddocks will be grazed within the first two weeks following turnout, then use bagged fertiliser. Slurry will only spoil grass, lower utilisation and delay grazing.
For heavy covers, graze first, then apply fertiliser. In March, growth will be low, so there is little point going with more than 25 to 30 units/acre of nitrogen.
Avoid using slurry and chemical fertilisers with potash on paddocks where spring-calving cows will graze, as there is an increased risk of tetany.
10 Magnesium
Regardless of whether potash was applied or not, make sure any cow which is producing milk is well covered for magnesium.
Spring grass is low in fibre, rapidly digested and excreted, so cows may not have enough time to absorb enough magnesium from forage. Big swings between day and night-time temperatures can also trigger tetany in cows.
There are various ways to supplement magnesium at grass, so choose the method that is most effective and practical for your system.
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