Drill protein crop from late April
By Simon Wragg
DRILLING dates for lucerne are approaching for those producers looking to increase proteins fed from home-grown sources.
According to independent nutritionist, Gordon Newman, lucerne can be drilled from late April through to August. Seedlings must be established before frosts start later in the year, he warns.
"Lucerne can generally be grown in the same areas as maize," he says. Ideally soil should be pH 6.5. If acidic, apply lime before drilling.
"All seed is imported and growers must check supplier recommendations for inoculation with Rhizobium meliloti," warns Mr Newman. Also, check seed has been fumigated against eelworm.
Wilts grower, Tim Mallet of Dean Farm, Sailsbury, has discussed with Mr Newman the merits of the 10ha (25 acres) of lucerne he grows to make silage for the farms suckler herd. He says it requires a firm, fine seed-bed. "Seed-beds should be similar to those for grass seed."
Seed rates should be about 20kg/ha (8kg/acre) and drilled to a depth of 0.5-1.2cm (0.3-0.5in).
To compensate for low yields in the first year, Mr Newman says lucerne can be undersown into spring forage crops of barley, wheat and semi-leafless peas.
"It will qualify for area aid if undersown, but drilled on its own it wont," he advises. However, avoid undersowing into grass leys as theyre too competitive and weed control can be difficult.
Best practice when undersowing is to allow the nurse crop to become established first. After weed control is completed, broadcast lucerne seed and then roll or harrow it in.
However, seed rates of cereal nurse crops must be reduced by 25% to stop lodging of lucerne seedlings, he advises.
At drilling, introducing tramlines will help limit crop damage, suggests Mr Mallett. "Lucerne recovers slowly when driven on." Tramlines also help ensure accurate fertiliser and spray application.
Like many legumes, lucerne requires a single nitrogen application of 50kg/ha (40 units/acre) to help with establishment.
Thereafter, potash is the major requirement and can be supplied from slurry applications. Also, a sulphur dressing of 10kg/ha (4kg/acre) is needed each year.
Weed and pest control is essential, adds Mr Mallet. Wild oats, blackgrass and barley have been treated with Laser at 0.75 litres/ha and springtails (similar to flea beetle) are treated with Steward at 1.8 litres/ha. "Gramoxone can be used at low rates later in the year."
A booklet is available entitled Lucerne: Practical agronomy and nutritional benefits to UK farmers, from the Royal Agricultural College, Cirencester (01285-652531).
Wilts grower Tim Mallet (left) with consultant Gordon Newman… weed control is essential for a good start.
• Firm, fine seed-bed.
• Undersow to get area aid.
• Check suppliers instructions.