As with the earlier part of the season, the focus should still be on minimising dry matter (DM) losses and maximising quality when making late-cut silage.
Even if you think you’ve got enough silage to last the winter, don’t skimp on the effort you put into making autumn grass silage cuts, reminds Volac silage expert, Ken Stroud.
Just because it’s late-cut grass doesn’t mean it’s any less important, he stresses. There can be plenty of potential in these cuts.
“Although autumn-cut grass can be difficult to wilt, it can be high in energy and protein,” he said.
“Even if feeding late-cut grass silage to youngstock or dry cows, they still need good silage too.
“Also, don’t overlook the importance of ensuring you have good stocks of silage available. If we have a poor spring next year and turnout is late, having a few extra tonnes of quality silage conserved could prove a lifeline.
“Good silage puts you in a stronger position to rely less on purchased feed.”
Efficient fermentation
To lock the maximum DM and nutrient content into silage, Ken contends that achieving an efficient fermentation with later cuts remains essential.
If undesirable bacteria are allowed to take hold in silage, they feed on sugars and proteins, and some compounds produced by bad bacteria make silage less palatable, he notes.
“Cutting grass at the optimum time, effective wilting and effective consolidation will help, but dominating the fermentation with beneficial bacteria from a proven additive is also key,” he said.
“The additive Ecosyl, for example, delivers one million beneficial Lactobacillus plantarum MTD/1 bacteria per gram of forage treated and results in rapid production of lactic acid, which quickly inhibits undesirable bacteria.
“In research, Ecosyl typically halves DM losses in grass silage, with the resulting silage also more digestible, which means more energy for milk production, and higher in protein compared with untreated silage.
“Across a range of forages, cows fed silage conserved with Ecosyl also yielded on average 1.2L more milk/cow/day.”
To help when making later silage cuts, Ken has provided some practical ‘dos and don’ts’.
Dos and don’ts for late-cut silage
Don’t be tempted to ‘shave’ fields; don’t cut them too low, for example if looking for extra bulk.
This is for several reasons:
- The lower part of the stem is less digestible – so has less nutritional value;
- Leaving a low stubble means the grass that’s been cut will be lying closer to the soil surface. This risks soil bacteria getting into the clamp and spoiling the fermentation. In contrast, a longer stubble that lifts grass off the soil helps air to circulate and can speed up wilting;
- If grass is cut below the bottom leaf node, it impairs its ability to recover and regrow.
Do wilt to the optimum %DM: Later grass cuts may be lighter, but the days are getting shorter and cooler with heavy dews, so it can be more difficult to get up to the optimum 30% DM content unless it is windy.
Speed up wilting times by tedding as soon as possible after cutting, and make sure you monitor DM content regularly. Don’t be tempted to over wilt to get to a high %DM, as this increases in-field losses.
Treat with an additive and aim to ensile within 24 hours.
Do chop to the correct length: A shorter chop length (e.g. 2-2.5cm) not only helps consolidation it also helps to release more sugars, which aids the fermentation.
Don’t neglect a quality additive: As mentioned, as well as improving fermentation, treating with Ecosyl has been shown to half DM losses, conserve more true protein, improve digestibility and silage intakes and, ultimately, increase milk yield per cow per day.
Remember, you only treat the number of tonnes of grass you harvest, so it’s no more expensive per tonne than treating earlier cuts.
For more information on Ecosyl products, click here.
