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LUCERNE ~ high protein silage
Why grow Lucerne
Drought tolerant- deep rooted Lucerne ( Alfalfa ) thrives in drought conditions with excellent yields particularly in dry seasons.
- High protein content around 20-22% makes a valuable contribution to any mixed forage diet.
- Mainly silage cutting, big baled or clamped, with some aftermath grazing. Three to four silage cuts per year, cut at 6-8 week intervals. Yields up to 15 tonne DM/ ha per annum. Typical Dry Matter 60-62% and ME 10-11 MJ/kg D.
- Improves soil fertility and benefits future cropping.
- Usually lasts 4 years.
Soil type
Requires deep, free-draining soils where a firm, fine seedbed can be prepared. Useless on unfissured rock or where pans exist and will not tolerate waterlogging where it can die out rapidly.
- Needs a pH of at least 6.5 to 7.0 in the topsoil, and a subsoil minimum pH of 6.0 to at least 30cm deep. Lucerne cannot tolerate acid conditions but thrives on chalk and limestone
Sowing Lucerne
- Lucerne seed needs to be inoculated with a suitable strain of rhizobia bacteria just before being sown.Our varieties are now mainly pre-treated with inoculant.
- Can be sown alone to allow chemical treatment of weed grasses, or with a non-aggressive companion grass which can smother weeds and also help with silage fermentation.
- Suggested companion grasses include meadow fescue and timothy, although the higher sugars in a tetraploid intermediate perennial ryegrass could be helpful in ensiling.
- Suggested seed rates are 8kg/acre lucerne alone or 6kg/acre lucerne drilled 10-12mm deep in rows 100-180mm apart, with 2kg/acre companion grass cross drilled to avoid close competition with the young lucerne plants. Can also be sown with red clover as companion.
- Sow between late April and mid July. Seedlings need to start winter well established as winter kill can reduce plant population in late sown slow developing crops. Best sown in spring in the North and Midlands and during the summer in the South. Can be undersown with 40kgs/acre ( half rate ) of spring barley to be cut for silage.
Varieties
Two high performance varieties giving very high yields with excellent protein levels and good disease resistance. These varieties are now mainly pre-treated with inoculant. (Nitragin Gold)
Lucerne Crop Management
- Established stands should be allowed to develop a large bulk before cutting, with first cut taken around mid May as soon as flower buds appear. Subsequent cuts should be taken not later than the opening of the first flowers ( 6 weeks ). Delayed cutting will give a more fibrous material seriously reducing digestibility. Cutting too early can weaken the stand and over frequent cutting can kill it. The crop needs to be cut leaving an approx 8cm stubble.
- Lucerne has a low soluble carbohydrate level and on ensiling one needs to be aware of possible fermentation problems. Use an approved additive.
- Autumn management is critical. The crop should be rested for 8 weeks from the end of August to the end of October to allow a build-up of root reserves. Crops can then be grazed or cut, or allowed to die back.
- Seedbed fertiliser treatment will depend on soil index, but Nitrogen is only worthwhile on Nitrogen index is 0 or where a companion grass is used.
- Maintenance fertiliser will again depend on soil index, with a P and K requirement of up to 60kg/ha per annum.
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