By Debbie James

GROWING lucerne is allowing a Pembrokeshire dairy farm to be self-sufficient in protein and provide variety in the cow ration.

With its high yield and high protein characteristics, lucerne has proved to be the ideal forage crop at Manor Farm, on the St Davids peninsula.

The Jenkins family first grew the legume 20 years ago after a succession of dry summers compromised grass silage yields.

Whilst they were attracted to the crop’s high protein content initially, they discovered that it contributed a high level of fibre to the TMR ration for the herd of 250 high yielding Holsteins.

“It gives cows girth and really slows everything down which is a big plus when you have red clover and other fizzy feeds in the diet. It reduces the volume of straw that we need to feed,’’ says Paul Jenkins, who farms with his parents, Colin and Margaret, and his uncle, Haydn.

“Since growing lucerne we have been able to reduce our purchased protein in the ration.’’

Manor Farm covers 800 acres with 68 acres of these devoted to growing lucerne.

Two hundred acres of wheat and barley, both spring and winter varieties, are also grown with lucerne providing a useful break crop in the rotation. It is also kind to the soil.

“The roots are enormous; they really open up the soil and improve the soil structure,’’ says Paul. “Lucerne draws up minerals from the ground because it is rooting down as well as fixing nitrogen.’’

The lucerne seed, supplied by PRAg Ltd, is drilled at the end of April and grown with a nursery crop of spring barley as a means of controlling weeds. No artificial fertiliser is used in the seedbed - only slurry and farmyard manure during its establishment.

The crop yields at least three cuts of silage, sometimes four, with the first cut in mid-May producing the heaviest crop.

The crop is mown but not tedded. “The leaf is easily shattered so you have to nurse it,’’ Paul explains. “We cut it, then row it up the following day so it has 48 hours to dry before we pick it up.’’

As an aid to preservation, the lucerne is treated with inoculant when it is baled.

At Manor Farm, the lucerne is baled and the first cut produces an average of 10 750kg bales an acre, reducing to six at the second cut and four at the third.

Last year’s first cut analysed at 48.7% dry matter, 21.12% crude protein, 43.4% NDF and an ME of 9.6 Mj/kg.

The Jenkins family grow all their own forage crops, including 65 acres of red clover mixture.

The chopped lucerne is fed selectively depending on milk yield - bigger quantities are fed to cows producing the highest volume of milk.

The herd calves all the year around, yielding an average of 9,000 litres at 4.2% butterfat and 3.4% protein, with milk sold to Glanbia.

TMR, which includes lucerne, grass, red clover and wholecrop silages, is fed with blend up to a maximum of 7kg throughout the year but grazed grass is maximised when possible. Cows are fed to yield in the parlour, up to 7kg.

In the 20 years that the farm has grown lucerne, it has mostly flourished; last year’s third cut was the only exception. Paul says a reason could be down to lucerne not performing well in wet conditions. “It does well in dry soil so we avoid wet fields. It seems to fail in any wet patches we have in the fields.’’

An additional benefit of growing lucerne in an arable rotation is that if it is grown as a single crop it can be used in the greening calculations.

“Greening was introduced as part of the Basic Payment requirements after we started growing it so it was a big plus for us,’’ says Colin. “Lucerne and red clover both extract nitrogen from the air and fix it.’’