tractor working grass
 Source: Taarup

Tips:

  • Mow after dew has dried off, at the time of ear or panicle emergence of the dominating plant
  • Avoid soil contamination, do not set mower or pick up reel too low
  • Cut at height approximately 5 - 10 cm depending on risk of soiling
  • Wilt quickly to 35-55% DM, no more than 24 hours for grass and 48 hours for legumes such as lucerne and red clover.
  • Spread the forage in as wide a swath as possible, within 1 hour of cutting.
  • Add an additive to control the fermentation and reduce in-silo losses

Time and Height of Cutting

For high quantity bale silage, the time of cutting depends on plant development. The energy contents are the highest between stem elongation and the emergence of ear or panicle of the dominating plant species. Cutting at the right time ensures that plants can rapidly re-grow, maximising annual yield.

At the latest, the crop should be cut when the plants are beginning to bloom. If the grass is too old and starts becoming woody, the crude fibre content increases and it becomes more difficult to compress the fodder.

The following table shows that delayed cutting results in a loss of energy in the fodder and a direct impact on the performance of dairy cows and feeding cattle.

Delayed cutting and resulting consequences for milk production
Delay of optimum time for cutting Loss of energy density MJ NEL / kg dry matter Reduction of potential milk production in kg / ha per year
4 days - 0.3 -   850
7 days - 0.5 - 1 420
10 days - 0.8 - 2 271

Source: Hoffmann, A., and Grote, D.: Management of Fodder Harvest, Claas Academy

The cutting height should be tailored to soil conditions and presence of potential contaminants. To reduce the risk of contamination, the cutting height should be between 5 cm. and 10 cm. Mowers that are able to closely follow ground contours are best.

If the cut is made too deep ("razor cut"), any equipment used to collect the fodder will need to be regulated accordingly and set to low working height levels. Contaminants can also get into the fodder more easily, causing mal-fermentation of the fodder and potential health threats to the livestock.

Furthermore, if cutting is too deep the crop will not be able to quickly re-grow as the remaining surface for assimilation is too small.

Download "Time and Height of Cutting Guide" in English (272KB - PDF) or Polish (231KB - PDF)

Pre-Wilting

The most important objective of pre-wilting is to achieve a dry matter content of 35% – 55%. This enhances the ensiling processes and reduces the breakdown of protein as well as the amount of fermentation fluid. The figure below provides guidelines for estimating dry matter content:

Form a ball of silage and place it in your hand. Then squeeze it once with both hands.
If you get DM content is:
Strong leaking of fluid already under light pressure < 20 %
Strong leaking of fluid under tight pressure 25 %
Leaking of fluid between fingers, hands get wet 30 %
No fluid leaking between fingers, hands become only moist 35 %
Hands barely glisten 40 %
Only a slight feeling of moisture in the hands 45 %
Hands remain completely dry > 45 %

Source: Müller, J., 2003: “Remarks about ensiling...”, following DLG-Information, 1999

The pre-wilting time should be kept as short as possible in order to stop yield losses due to the breakdown of sugar in the plants. The taller the grass, the higher desired dry matter content and the less favourable the weather, the longer pre-wilting will take — this is outlined in the table below.

Required duration of pre-wilting according to weather conditions
Height of the grass Favourable weather conditions and desired dry matter content of Unfavourable weather conditions and desired dry matter content of
30 % 40 % 30 % 40 %
High 6 hours 11 hours 12 hours 22 hours
Medium 4 hours 8 hours 9 hours 15 hours
Low 3 hours 5 hours 6 hours 11 hours

Source: Fübbeker, A., and Müller, J., 2003: “Remarks about ensiling...”

In very favourable weather, 4 to 6 hours can be enough. If, however, the grass is dried too quickly in such conditions, losses due to crumbling during tedding, turning, swathing and baling increase. In addition, material with dry matter content higher than 55% becomes increasingly difficult to compress. With 65% dry matter, lactic acid fermentation becomes insufficient.

So-called conditioners accelerate the pre-wilting process by crucial hours. These machines mow the plants and at the same time treat them in a way that opens the leaf surface and increases evaporation.

An unconditioned crop should be treated and spread broadly with a hay tedder as soon as possible after mowing to ensure better drying. In the case of large yields, it is particularly important to use a swath turner to ensure that the crop dries evenly and to avoid wet and poorly wilted portions close to the ground.

The windrower is used immediately ahead of the baler. The swath should be about as wide as the pick-up of the baler and contain slightly more material on the outside compared to the middle of the swath. Pre-wilting can also be prevented by swathing. Early swathing can help to avoid excessive drying in cases where the baler is not immediately available.

Download the "Pre-wilting and Estimating DM Content Guide" in English (273KB - PDF) or Polish  (195KB - PDF)

Further guides and other pieces of literature can be downloaded here or from our literature page.