When it comes to grazing systems, rotating livestock around multiple paddocks is the most effective way to manage grass.

As cattle are regularly moved to fresh grass, they become accustomed to regular handling. But the biggest benefit is the positive effect on liveweight gain and milk yield, as well as cow fertility.

Assuming store cattle gain 1kg/day of liveweight over a 180-day grazing season, a conservative 10% increase in weight gain produces an additional 18kg/head, worth £54 at a mart price of 300p/kg. For a group of 20 stores on a 15ac grazing block, that is an additional £1,080 a year, and goes a long way to paying for extra drinkers and fencing materials.

Rotational grazing also increases the amount of grass grown on paddocks. As animals move off a paddock, the intermittent rest-period allows grass plants to regrow and build sward covers again.

AFBI trials saw paddocks grazed on a rotational system yielding 10.2t DM/ha over the year, compared to 6t DM/ha on set-stocked paddocks, with each system receiving identical fertiliser rates.

Higher grass yields can support higher stocking rates, provided ground conditions permit; or alternatively, fertiliser rates can be reduced to provide an economic saving.

For farmers looking to try rotational grazing this year, outlined below are 10 tips to help with the process.

1 Start off with one grazing block

Trying to do too much too soon creates problems, and farmers are more likely to abandon rotational grazing when this happens. Therefore, start with one grazing area and a single cattle group.

Focusing on one grazing group gives farmers time to hone their grassland management skills during the course of the season.

Choose an area around 15ac to 25ac in size, and preferably on a drier part of the farm in the first year. Once confidence grows, paddocks can be extended to other grazing blocks on the farm.

2 How many paddocks are needed?

Aim to move cattle to fresh grass at least twice a week. This means moving animals every three days.

In spring and summer, once a paddock has been grazed out, aim to give a rest-period of between 18 and 21 days.

So, a minimum of six paddocks will be needed – although a seventh paddock gives more of a buffer for someone trying rotational grazing for the first time.

3 What size paddocks do I need?

Don’t get too hung up on what size to make the paddocks.

Paddocks should be flexible in size as grass growth will start off low in spring, peak in June, then tail off in autumn.

Use electric fencing to split paddocks into smaller grazing areas once grass growth surges ahead of demand.

Temporary wires can be removed later in the season as growth slows, giving cattle a larger grazing area to roam over.

As a rule of thumb, for a three-day grazing allocation, paddocks around 2ac and 3ac in size work best when starting off.

4 Moving cattle to fresh grass

The objective with rotational grazing is to keep moving cattle to fresh grass before swards get too strong and forage quality declines.

If cattle repeatedly enter swards of knee-high grass, either reduce the size of the paddock or increase the number of cattle in the group.

Moving animals every three days is more practical in spring and late summer. However, as grass growth peaks in May and June, cattle will need to be moved every 24 to 48 hours.

Sticking rigidly to the three-day period during peak growth means that swards in the paddocks ahead will get too strong, reducing utilisation and leaving rejected grass that needs topping.

5 Rotation length

In April to early May, a rotation length around 21 days is recommended. This means that when cattle enter a specific paddock, they should re-enter it three weeks later.

But as grass hits peak growth, reduce the rotation length to between 12 and 15 days to prevent swards getting too strong.

Once the period of peak grass growth has passed, usually from mid-June onwards, the rotation should be increased back up to around 18 to 21 days.

The rotation should be increased to 25 days by 1 September and 30 days come October.

6 Pre- and post-grazing covers

The best way to maintain sward quality is to move cattle to a new paddock once grass covers reach 10cm to 12cm in height, which is just above ankle height.

At this height, pre-grazing covers are between 3,000kg to 3,200kg/ha of dry matter (DM) depending on how dense the sward is.

Graze down to a residual cover of approximately 4cm to 5cm, which is basically around toe height.

When cattle enter paddocks above the recommended pre-grazing cover, it is difficult to clean out swards within a set time period of three days.

Rejected grass will need topping. When cattle enter paddocks below the recommended cover, clean-out will improve and topping is rarely required.

7 Dealing with a surplus and deficit

During peak growth, grass will beat cattle and swards will be getting too strong for grazing.

Skipping these paddocks and removing surplus grass as baled silage takes a big leap of faith for a beginner to do during rotational grazing.

The key is to take out the surplus early. Paddocks will then be ready for grazing within three weeks. The longer you delay cutting, the stronger the grass gets.

When grass is eventually baled, regrowth is slower and it will take longer for these paddocks to be available for grazing again.

By walking paddocks every week, it is easier to identify when growth rates are low and a deficit is likely.

This allows early action, such as more fertiliser to be applied, cattle numbers to be reduced, meal to be introduced or an extra paddock to be brought in into the grazing block.

8 Water

Providing water in every paddock is always an issue when starting out with rotational grazing. All too often, fields have a single drinking trough placed in one corner of a field.

This does make it more awkward to split a field in two – but not impossible. Set up temporary fences diagonally to access the drinker if necessary.

Moving troughs to a more accessible point is also recommended. When installing additional troughs, locate them so they service multiple paddocks.

Run new water piping over ground to cut down on setup costs. This way, if the trough has to be relocated, the process is straightforward.

9 Mains electric or battery fencing?

Mains electric is the best option for controlling cattle when rotationally grazing, but not essential. Battery fences work effectively, but are usually more expensive than a single mains unit.

Choose a battery fence with a solar charge to extend battery-life and opt for a unit with higher voltage.

10 Fertiliser

Keep on top of fertiliser allocations. Where fields are split into smaller divisions, it will be more practical to go with a blanket dressing of nitrogen across the whole grazing block at regular intervals, as grass growth dictates.

Read more

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Five tips to get spring grazing back on track