Paul Macer of Kite Consulting urges farmers to think about implementing a multi-cut approach to silaging this year.
Hannah Noble finds out more…
The multi-cut system of silage making usually consists of four or five cuts rather than the traditional three-cut system.
“A multi-cut system allows farmers to grow more forage of better quality. I also allows increased forage inclusion rates in diets, better land utilisation and reduces the risks posed by volatile feed markets, high concentrate to forage ratios and the weather.
“Take advantage of a shorter weather window than with more traditional cuts by targeting a 24-hour interval between mowing and harvesting.”
“While cost per acre will generally be higher in a multi-cut system, due to the higher levels of inputs and greater harvesting costs, the higher dry matter (DM) production over the season means there is a cost benefit just on the amount of material utilised.
“When the extra energy produced is calculated it shows the multi-cut system will produce 50 per cent MJ/acre more than a traditional three-cut system. This leads to a 14.5 per cent reduction in cost per MJ.”
“Cutting grass in the first weather window in May, and targeting subsequent cuts at 35-day intervals, or less if the weather is suitable will help.
“Sward cutting height should be targeted at five to seven centimetres as residual photosynthetic rates are crucial, especially in new leys.
“Cutting too low increases the potential for drought stress, as the plant will redirect energy for root growth towards new leaf growth.”
There is potential to lose up to 14 days regrowth time if there is no residual leaf left, resulting in losses up to 1,000kg DM/ha/cut.
“Aim to achieve a target dry matter of 35 per cent within 24 hours of mowing. Tedding should be carried out according to weather conditions and the weight of the crop. Where necessary grass should be spread straight after mowing to allow the maximum surface area to be exposed to the elements during the crucial two hours that the plant’s stomata are open.
“Chop length will depend on the DM of the crop. Wetter crops will require longer material in order to avoid them turning to a mush, but intakes are usually higher with a shorter crop.
“Remember DM can be quickly tested using a microwave to dry down the crop.
“When it comes to clamping the silage fill the clamp in long, shallow layers as opposed to the traditional wedge. Put an extra tractor or use a specialist compactor on the pit where possible and target a density of 250kg of DM/m of clamp. If possible clamp multiple cuts in the same clamp as this will lead to a more consistent diet during feed out.”
|Three cuts||Five cuts|
|Yield and DM|
|Dry Matter (%)||28||35|
|Dry matter (tonnes DM/acre)||4.2||5.95|
|Clamp losses (%)||10||10|
|Amount fed (tonnes DM/acre)||3.78||5.35|
|Energy ME (MJ/kg DM)||10.8||11.7|
|Protein (% in DM)||14||16|
|Freshweight cost (£/tonne fed)||35.5||41.2|
|DM cost (£/tonne fed)||127||118|