Grass conservation

Why do we need to conserve grass?

Silage Silage making is the conservation of wet forage. The ensiling process preserves a high proportion of the nutritional value of the green fresh forage. Has increased in popularity over last 4 decades.

Silage making process Conservation of herbage through an acidification process caused by the production of organic acids, primarily lactic acid produced by epiphytic bacteria fermenting released plant sugars.

Fermentation process Aerobic stage - last for a few hours after ensiling, oxygen is reducing Anaerobic stage – all oxygen used up, lactic acid bacteria dominate and pH reduces Storage stage – acidic conditions limit microbial activity Feeding stage – exposure to air and aerobic spoilage may occur

Silage Very important to start with good quality forage Sugars Dry matter

Grass is mown

Left in field to ‘wilt’

Picked up by forage harvester

Consolidated to remove air

Covered to keep air out

Compressed bales

Additives/inoculants

Chop length is important

Clamp face management

Analysis

Feed out

Silage: Feed out Expose only the area that is needed on a daily basis Using narrow clamps will reduce the area of the exposed face Aim to get across the face every 3-7 days and take it back by at least 2m per week to avoid secondary fermentation Use a shear grab rather than a front loader to keep a tight clamp face

Silage effluent

Silage: effluent management Highly polluting Corrosive Loss of nutrients

Silage: effluent management Waste Biochemical Oxygen Demand (mg/litre of oxygen) Whole milk 100,000 Silage effluent 65,000 Pig slurry 25,000 Cattle slurry 17,000 Dirty yard water 1,500 Raw vegetable washings 500 – 3,000 Dilute dairy & parlour washings 1,000 – 2,000 Raw domestic sewage 300

Silage: effluent management Crops ensiled at 25% DM will produce very little effluent Crops ensiled at 18% DM will produce up to 100 litres/tonne/day Crops ensiled at 15% DM will produce up to 200 litres/tonne/day

Silage: effluent management Most effluent will be produced in the first 10 days after ensiling Can be spread to land diluted 1:1 with water and applied at a rate of 25-30m 3 /ha Must not be spread close to boreholes and watercourses Do not mix with slurry in a confined area as it will release toxic gases

What other crops can we make silage from?

Forage maize

Wholecrop cereals

Haymaking

Preservation of grass by drying to a moisture content of <18% The first step in hay making is the mowing of the grass crop. This usually starts in late June just before flowering. Cutting must be done when the weather is fine and several continuous dry days are expected. Hay that has been rained on is of poorer quality and may be unpalatable. After the crop has been cut it is allowed to dry in the sun. To facilitate this a tractor with a "hay bob" will drive over the cut rows to rough up the drying grass. This helps remove moisture more quickly and makes the baling operation easier to complete.