Timing the harvesting right is vital

Timing the harvesting right is vital

Silage production Part 2


This is a vital step in the silage making process, as soon as the grass is cut it will start to lose nutrients but it needs to dry out before it can be ensiled effectively.

No matter how good our Silostop films are at keeping out oxygen and maximizing the quality of the forage in the clamp if the crop is cut too early, over wilted and really dry or ensiled very wet it will never be at its best. If quality doesn’t go in quality cannot come out.

The trick is to getting the optimum period of drying so the crop can be foraged and ensiled at its best. This article is a summary of the stages and points to consider.


Cut grass and legume crops in the afternoon, avoid soil contamination. Wilt in the field for 24 to 48 hours in spread swaths. Do not turn or shake swaths.

When to cut
Cut grass, clover and lucerne in the afternoon when sugars are at their highest level.
Avoid rain-soaked or dew-covered crops.
Cut maize at 32-36% DM, and cut whole-crop cereals at 35-40% DM.

Cutting height
Roll fields early in the season to reduce the risk of an uneven soil surface and stones, which could contaminate the crop.
Avoid cutting too close to the soil surface. Cutting very close to ground level increases the risk of soil contamination.
Increasing height of cut:
- reduces dead plant material.
- increases silage digestibility.
- speeds re-growth of perennial crops.

Field-wilting grasses and legumes

Optimum time from cutting to pick-up
The optimum period of time between cutting and pick up is 24 to 48 hours for grass crops and 48 to 72 hours for lucerne and red clover.
During wilting grass typically loses 1 percentage unit of digestibility per day in the field through plant respiration; the loss is greater in wet than in dry weather.
Wilting to 30% DM at harvest will virtually eliminate liquid effluent loss after ensiling.
Most grass crops will achieve 30% DM within 48 hours after cutting.


Water loss is most rapid in the first 2 hours after cutting when leaf pores are open.
Narrow swaths result in slow wilting because water cannot evaporate from the centre of the cut swath.
Spreading the cut crop immediately after cutting maximises the speed of water loss.
Spread crops should cover more than 75% of the total field area.
Rainfall on the spread crop evaporates rapidly after rain has stopped.

tractor spreading grass

Turning and shaking (tedding)

Turning and shaking are less effective ways of removing water from the cut crop than spreading.
Shaking (tedding) increases loss of leaves (and valuable protein), especially with lucerne and red clover.
The link below will take you to a video with a more in dept look at the process:
click here