Farm industry could save £500m pa
LEGUMES have received less interest in the UK than in the rest of the world, but that may change now the milk price has fallen.
Independent nutritionist Gordon Newman told last weeks Genus National Forage Conference, at the Royal Bath and West Showground in Somerset, that legumes attracted little publicity and research because they were of limited interest to the feed and fertiliser industries. Estimates suggested a legume-based system would save the farming industry £500m a year and cost the feed and fertiliser industries £330m a year, he claimed.
Research into legume crops, which could reduce reliance on concentrates and fix their own nitrogen, must be funded by producers.
"Legumes have not been important here," he said. "Milk price has steadily risen and nitrogen fertiliser has been cheap. But, now the reverse is happening, legumes will become more important to profit."
He said that anywhere you could grow maize you could grow legumes. White clover had a role, but lucerne and peas must now be looked at.
The benefits of feeding legumes are that cows will have higher feed intakes when two forages are fed, reducing liveweight loss and increasing milk yields. And although legumes have lower digestibility than ryegrass, digestibility declines more slowly with maturity and legumes break down more quickly in the cows rumen. The high level of rumen degradable protein in legumes also aids rumen bacteria activity.
Although bloat is a risk when legumes are overfed, organic producers have shown that bloat need not be a problem.
Lucerne is the most promising legume, said Mr Newman. It can be zero-grazed, strip grazed or silaged, and, being deep rooted, can maintain yield through a summer drought.
But lucerne does not like wet roots, weed competition or growing in acid soils. It is best grown in otherwise unproductive thin chalk, limestone or sandy soils.
He advised drilling after winter barley or oilseed rape, but before August 10, or undersowing in maize, cereals or peas to compensate for its low yields in the first year.
The crop should flower once before it is first cut, but thereafter it should be cut at the pre-bud stage when there is still fermentable carbohydrate in the sap.
Round baling lucerne silage improves its fermentation stability compared with clamping the crop, and, well made, the silage can have a high crude protein of 22%. He also said bacterial additives had improved lucerne silage nutritionally in Italian studies.
• Best on alkaline, chalky or sandy soils.
• Drill before Aug 10.
• Allow to flower before first cut taken.