27 March 1998

Silage finish leaves organic farm in clover

Reliance on red and white clover silage has allowed one

farm manager to finish cattle at a cost of only 40p/kg

liveweight gain. Emma Penny reports

HIGH quality clover and grass silage has allowed one farm to finish beef cattle over-winter with no other supplements.

The reliance on red and white clover at Elm Farm Research Centre, Newbury, Berks is explained by farm manager Richard Jacobs. "We are a charitable trust developing and promoting organic agriculture, and are trying to develop a beef system which reflects best practice."

Progeny from the 70 sucklers at the 93ha (230-acre) Elm Farm are finished and sold deadweight through the Organic Livestock Marketing Co-operative. Carcass weights range from 240-340kg, grading mainly from R4H to O4L, says Mr Jacobs.

"This year the cattle have finished off red and white clover silage alone – we put 10t of triticale in the barn for feeding this spring, but have not needed any of it. I also felt that cattle fed cereals last year finished too quickly, so carcass weights were consequently low."

Liveweight gains

Average daily liveweight gain for both heifers and steers on the clover silage ration is 0.9kg. Mr Jacobs reckons the rations cost 38p/kg and 40p/kg liveweight gain for steers and heifers, respectively.

"If we had fed triticale at 2.5kg a day for steers and 1kg a head for heifers the cost a kg gain would have risen to 51p and 41p, respectively.

"Finishing cattle on silage alone has given substantial savings, but silage quality is vital; if it had been lower we would have introduced the triticale."

First cut at Elm Farm analysed at 33% DM, 11.2 ME, protein of 17.5% and an intake factor of 121%. Second cut was less good at 23% DM, 8.9 ME. 19.6% protein and an intake factor of 85%. "But second cut appears to be feeding better than it analyses."

Both red and white clover mixes are grown at Elm Farm. While the red clover and ryegrass mix – containing Merviot red clover, and ryegrasses Fetione and Tivioli – is taken predominantly for silage, the white clover/ryegrass ley – with clovers Alice and Menna, and ryegrasses Fetione, Hercules and some Timothy – is used for grazing, with some shut up for silage.

"Clover is leguminous and fixes nitrogen. It, therefore, builds fertility in the soil for following cereal crops, an important factor where no N is used, as well as providing quality grazing for cattle."

Much of the land at Elm Farm is marginal. The high clay and silt soils are only slowly permeable, meaning they are often waterlogged and prone to cultivation damage.

"White clover is fairly long term and is grown in fields where we would be lucky to get a cereal crop every five to seven years. Red clover does better under shorter rotations, and is sown on the better land."

Preparations for silage start in late March, when slurry is applied, usually at under 22,000 litres/ha (2000gal/acre). "Our slurry tank is open and so collects a lot of rain water. Consequently the slurry is rather thin, really more like dirty water, but it does help to bulk up the clover and grass."

Silage is cut using a contractor in late May, with both red and white clover leys cut at the same time. While some might suggest that this compromises ideal cutting date, Mr Jacobs takes great care to ensure all crops are at their optimum when they are cut.

"It is difficult to get a contractor to come and do bits and pieces, and would add significantly to costs. It would also make clamp management more difficult," he says.

Last season, a dry spring meant first cut yields were much poorer than anticipated, at about 3.2t DM/ha (1.3t DM/acre), while second cut yielded 6.2t DM/ha (2.5t DM/acre). "In a more typical year we would expect yields to be somewhere between the two cuts."

Once cut, silage is wilted for 24 hours and then ensiled. No additives are used, although Mr Jacobs buys in some Live System inoculant which will be used in marginal conditions. "Being organic we are not allowed to use acids – Live System is rather like yogurt – full of naturally occurring bacteria."

Timing is crucial

Good consolidation is vital, and two tractors are used to ensure that it is. "When we break overnight we will cover the pit and then pull the sheeting off in the morning to refill it. But we aim to have the entire pit filled and covered within 24 hours or so."

Timing operations exactly is crucial to making high quality silage, stresses Mr Jacobs. "It is vital to get out and assess the quality and quantity available before cutting. Because we do not use nitrogen to kick-start growth, cutting date is often less straightforward than on conventional farms.

"The value of good contractors, who will come and cut silage when you want them to, is often underestimated. And when cutting does start, you must be quick, getting silage ensiled, consolidated and covered within as short a space as possible. With organic farming you cant use chemicals to get yourself out of sticky situations." &#42

Finishing cattle on silage alone has given substantial savings, says farm manager Richard Jacobs.

ORGANIC SILAGE

&#8226 Red and white clover.

&#8226 High daily liveweight gains.

&#8226 Quality vital.