5 April 2002

Dairy sward management

style, flock-friendly

Grazing sheep can benefit

from some of the sward

management techniques

more commonly used on

dairy farms aiming for high

yields from grass.

Richard Allison reports

REGULAR walking of paddocks and assessing sward heights is an essential ingredient for profitable sheep production on one Shropshire unit.

With a keen interest in sward management, John Parry manages a 380-ewe flock of northern England Mules, plus 60 ewe lambs. "Gross margins are currently about £55-£60/ewe due to a combination of good grassland management and achieving a lambing rate of a least 185%."

One grazing strategy adopted at Donington Farm is to group ewes according to age. "A five-year-old ewe is the equivalent to a 60-year-old person and needs more care. They often have poorer teeth and are less able to graze swards tightly."

An ideal sward height is 6cm (2.4in) as young ewes with a full set of good teeth can nibble grass down to 2.5cm (1in). Older ewes are grazed on longer grass as they are only able to graze down to 7.5cm (3in), he explains.

"The grazing area includes 20ha (50 acres) of non-IACS land, rented from the David Austin rose company. Perennial ryegrass leys, including 1kg/acre of clover seed are put down for five years between crops of roses to build up soil fertility."

Before this arrangement, grass was left ungrazed with occasional topping, but this led to swards thinning rapidly.

This restricted the process of building soil fertility before the next rose crop, he says.

A crucial factor in maintaining swards is to prevent poaching by taking animals off paddocks during winter, believes Mr Parry. "Ewes are housed in mid-December until lambing in February-March, while the remaining lambs are moved to beet tops and stubble turnips.

"When housed, ewes are fed ad lib grass silage and hay made from 10ha (25 acres) of poorer pasture located near the unit."

This silage area is also used for ewes after weaning in mid-July. Lambs are moved to worm-free grazing, allowing swards at the rose nursery to build up for flushing ewes in autumn. "A further 4ha (10 acres) of set-aside land is also used for flushing ewes in autumn."

At weaning, lambs are sorted and the top third pushed hard and fattened by autumn on the best grazing and concentrates. The remaining smaller lambs graze poorer fields with no concentrates to achieve slower growth rates. These are then wintered on beet tops and roots.

"Splitting the lamb crop helps with cash flow and the supply of grass in autumn," he explains.

To keep swards in good condition, cattle occasionally graze sheep paddocks. Without cattle, he believes stocking rates would have to be increased above the current 12 ewes plus lambs/ha (five/acre) to prevent swards from becoming mature and stemmy.

By maintaining appropriate stocking rates, the sward will remain at 6cm (2.4in), with tall dense turf and no severe dock or other weed problems. However, some knapsack spraying is required, he adds.

Fertiliser policy is also important to maintain spring growth and allow clover to thrive. Mr Parry applies 88kg/ha (70 units/acre) of nitrogen to boost spring growth at turnout. "There are no further applications, clover in the sward takes care of nitrogen supply for the rest of the year."

The secret to maintaining clover is to test soil pH and levels of P and K and correct where necessary. For most paddocks, soil is index 5 for phosphorus which means grass can fully use the nitrogen fixed by clover, says Mr Parry.

None of the grazing areas are IACS registered and grazing includes small fields in front of large houses, horse paddocks and rotational grazing at the rose nursery. He says most people with horse paddocks are simply looking for someone to look after grass and grazing with sheep often improves these swards.

"The reason we dont have much pasture of our own is that our land is IACS eligible and financial returns from sheep flocks are insufficient to justify grazing this land.

"Previously, we had grassland in a three-year rotation with sugar beet and cattle, but its now lost to arable cropping."

When a new paddock is taken on, the sward is assessed for grass type and density to indicate what stocking rate it can carry. "All fields slot within the overall grass management plan including poor pastures, which are useful for ewes after weaning.

"Even with high quality swards, ewes with lambs have to be fed some concentrates until June. The amount fed is continually reassessed, sometimes there are dry spells during May when more concentrates are fed to keep milk yields up." Mr Parry believes a ewe with twin lambs is equivalent to a high yielding cow and they are not expected to perform on grass alone.

Concentrate feeding ewes to increase milk yield is easily justified with the low price of cereals, believes Mr Parry. Lambs can obtain five times more energy from milk compared with concentrates or grass. Its milk that makes lambs grow and produce a more favourable killing out percentage at slaughter, he adds. &#42

MANAGING SWARDS FOR SHEEP

Graze according to age.

Daily walking of fields.

Cattle also graze paddocks.

SWARDS FOR SHEEP

&#8226 Graze according to age.

&#8226 Daily walking of fields.

&#8226 Cattle also graze paddocks.