Learning Outcomes:
- To describe the different ways of preserving grass.
- To explain the pros and cons of each way of preserving
- To explain what is needed to make good silage.
Methods of Preserving Grass
SILAGE
- preservation of green crops by a form of pickling – air and water ingress must be prevented
HAY
- green material that is cut and dried naturally in the field, needs air to help it ‘cure’ must be kept dry
HAYLAGE
- very dry silage or very damp hay, must be wrapped to prevent air and water ingress
DRIED GRASS
- best quality fresh material collected e.g Lucerne, heat dried, pelletted and fed as a concentrate – very expensive operation, not used much today
Nutritive Value of Grass…
Great potential to produce ‘cheap’ sources of energy and protein for farmed livestock. Good grassland management produces high yields of digestible nutrients. Reducing the need to buy in other expensive feedstuffs.
Grazing – cheapest option, but modern methods often means cows do not graze, food is brought to them – Zero grazing.
Short leafy grass is rich in protein and highly digestible. Maturity causes cell wall increase, increased fibre (stem) and decreasing levels of crude protein (in leaf). As grasses mature, photosynthesis creates a higher % of sugar, which makes ensiling mature grasses easier than young leafy grasses.
Making Hay
Making Silage
Silage Analysis
Digestibility ‘D’ Value:
Grasslands are usually analysed by assessing their Dry Matter (DM) content. Obtain a sample of fresh material, weigh it, drive off all the water and weigh remainder – this is the DM (Silage DM’s range between 26-35%)
D Value is the % of Dried Organic Matter that can be digested by livestock – aim for a D value 68 – 72
Below is presentation which gives more details about grass conservation.
