Grazing Plans

To plan grazing you have to understand how grass grows, how to measure growth and the livestock demands; available in the Assessing Swards section (LINK). Once you have that information there are three steps to building a grazing plan:

1. Calculate grass available for grazing = (pre-graze measurement – post-graze target) X field size (in ha)
2. Livestock allocation – based on dry matter allocation as a % of bodyweight (suckler cows = 2.5%, ewes with lambs = 3%)
3. Calculating how long the field will last = grass available for grazing ÷ daily requirement of group

More information can be found here.

Research at Rothamsted’s North Wyke site found ruminant livestock eat sporadically in the morning, preferring legumes to grasses. In the evenings they will fill up on grass in order to cud in the dark overnight. Grass dry matter is often better in the evenings, so aim to move livestock onto fresh grass late in the day to ensure good intakes of high quality feed.

This is when the livestock has unrestricted access to a wide area throughout the grazing season. This doesn’t require too much managing and the capital costs are low and can work well if target sward height is maintained. However, this system will lead to patchy areas that may not get grazed, lower forage yield as grass quality declines and weeds can start to build up.

This is when stock are moved around a number of smaller fields every few days based on sward height. It is less intense than paddock grazing but still requires regular monitoring and management.

The benefits of using this system are:

• Most of the forage in each field gets grazed
• Its flexible and can incorporate manure or fertiliser applications
• Surplus forage can be cut
• Can be used as a method of weed control
• Parasite control

This is when the field is subdivided into a series of paddocks, and the stock are moved around them based on sward height. This grazing system requires the most management, and monitoring, but sees the highest forage production and intense utilisation.

Focus farmer Richard Hawke from Launceston, Cornwall tried paddock grazing as part of the Healthy Livestock Initiative – Sheep Focus Farming and was surprised at how effective it was. He explains “I didn’t believe it myself at first but I tried it. I put 400-450 ewes on 1 acre for 24 hours for 100 days. The pasture recovered quickly. I used an electric fence with 3 lines and a wrapper system. I measure the grass using a plate metre, it’s better than a sward stick. I had escapees but I was honestly surprised by how successful it was.”

There are initial outlay costs for the fencing and additional water troughs, also the hassle of moving the fences periodically but this system has many rewards:

• High stocking rates can be sustained
• Weeds are kept under control
• The manure from the animal is more evenly spread in the field
• High utilisation of grass per ha
• Parasite control

Source: EBLEX Planning grazing strategies for better returns

This is a variant on paddock grazing where grazing requirements are very precisely allocated and a field is sub-divided into 0.1ha cells with stock moved every 1-2 days. This means that grass is intensively and efficiently grazed, with little wastage.

Technograzing was developed in New Zealand and is gaining popularity in the UK where our climate offers excellent grass growth. Studies in both New Zealand and Britain have shown a very good return on investment compared with traditional grazing techniques. (Read one here).

Agri-tech Cornwall is running a project at Rothamsted Research North Wyke in collaboration with Precision Grazing Ltd investigating the impacts of Technograzing on soil, water quality, biodiversity, pasture quality and livestock performance. More information can be found here.

Mob grazing is another form of rotational/paddock grazing. It involves tightly grazing livestock on pastures that have been allowed to grow to a greater height than they would normally be grazed at (typically 1-2 feet), with regular stock movements (each day) to fresh pasture and a long rotation.

The height of the vegetation is important; stock will graze much of the sward, but will also trample the rest into the soil which provides valuable organic material to boost soil health.

Mob grazing tends to work best with diverse swards; traditional ryegrass pastures do not have the necessary structure. Infrastructure is a crucial part of setting up mob grazing systems, with temporary fencing and water systems requiring careful planning.

This form of grazing can be a useful addition to arable rotations. Growing diverse crops and trampling them into the soil when mob grazing can improve soil health and fertility, and the temporary systems effective in larger arable fields. More information here.