The evidence that most grassland soils require the application of sulphur from fertilisers to maximise grass silage and grazing yields still mounts. Most farmers now appreciate that all light and medium soils, and even now some heavier loam soils, don’t release enough sulphur from organic matter to allow grass growth and quality to meet potential. They also realise that there is not enough available sulphur in slurries and manures to meet demand.
Quality grass is a cost-effective part of feeding and regular reseeding ensures that the required nutritional value of the ley is maintained. New leys can help deliver a 33% increase in yield in the first year compared to a typical old sward, and in a drought year this can increase up to 50%.
Destroy the old sward using a product containing glyphosate. Ensure there is sufficient new growth for the chemical to be taken up and that an appropriate rate is applied under correct conditions. Whilst this treatment will control actively growing plants it will not kill dormant seed in the soil.
Timing is imperative with overseeding and the main aim is to minimise competition from the existing sward, the best time to over seed is March, April, July or September as the grasses are not growing as vigorously as they are in May and June.
In recent times there has been some debate about the ideal chop length for rumen health. In this respect, a useful gauge for chop length is that it should be the width of a cow's mouth! However, only a maximum of 10 per cent should be this long. If there is too much long chopped forage cows will sort the ration and only eat the short chop. In terms of good compaction in a silage clamp, it is absolutely essential to alter the chop length depending on the dry matter content of the forage to be ensiled.