As a farmer, you want the best quality of feed possible for your cows. You want roughage with a good nutritional value that can be optimally utilised by the rumen.
Fertilisation of the pasture, type of grass, the moment of mowing and also the harvesting process itself are all important points for creating good-quality feed.
The moment of mowing and harvesting the grass
Harvesting silage starts with the moment of mowing. First of all, check if the grass is long enough to mow, but also not too long. A rule of thumb is that the seed plume should not be there yet, in order to have the best possible use of the silage.
The second important point is to have nice sunny and dry weather for a few days. Think about the number of acres and the capacity of your harvester. It should not take too long to harvest the grass, because in that case the silage becomes too dry. This does not benefit the quality of the grass. A field period of around 3 days is the maximum. Otherwise a lot of nutrients are lost.
Mowing length is also important. Do not mow too close to the ground, to have as little crude ash as possible in the silage. On the other hand, do not leave the grass too long. Around 5 cm is the average. If you mow the grass to a shorter level, regrowth is slower to start.
Silage bunks, bales and pits
There are several ways to store the silage in a suitable way. Round or square bales are easy to handle and store in any place you want.
With good baling equipment, which seals the bales and makes them airtight, the quality of the silage remains good for many months.
Other options are to store the silage in a bunk or pit. Most of the time, the bunk or pit contains a concrete floor and/or walls.
These concrete floors and walls are easy to clean and also very useful for creating a solid package of silage.
If the choice is to store the silage in a bunk or pit, there are a few main points to keep in mind.
If oxygen can enter the pit or bunk, the silage heats up. This results in a loss of energy, dry matter and quality. The better the silage is pressed, the less air the package of silage will contain. A rule of thumb is: Deposit thin layers of silage over the whole bunk or pit. 15 cm to 20 cm is the maximum for creating a high density. Keep in mind that the dryer the silage is, the thinner the layers should be to keep it pressed well.
The dryer the silage, the more energy and quality losses you have. Also, it is not easy to press dry silage into a compact and airtight package.
Keep an eye on the dry time of the silage, and think about what group of animals you will feed the silage to. Dairy cows, dry cows, young stock or beef animals: they all have their own nutritional needs.
The particle length is a key factor that is related to how dense the silage pit or bunk can be. If the particle lengths are long (>10 cm), it is more difficult to create a high density in the pit or bunk. Short particle lengths (<2 cm to 4 cm) are easier to press together. An additional benefit is that short particle lengths are easier to mix in a ration together with other feed types. Keep the number and quality of the knives in the harvest equipment in mind, especially for round bales.
Sometimes it is valuable to use a silage upgrader to improve the quality of the silage. For example, when bad weather conditions suddenly show up, or the dry matter percentage is too low because of bad weather in the autumn. In these conditions a silage upgrader is useful. You can add a bacteria mixture to reduce energy and nutrient losses. This does not mean that a silage upgrader is only useful when the weather conditions are bad. They are also useful for reducing energy and nutrient losses in general.
Pack and cover
The last step in the harvesting process is packing and covering the silage pit or bunk. After putting many thin layers with a high density into the pit or bunk, it then needs to be packed and covered in order to be airtight. With a thin plastic layer, the silage is covered precisely. After that, a second layer of stronger plastic should be applied to the pit or bunk as well.
To create an optimum density, covering with plastic alone is not enough. There should be a certain weight on the whole pit or bunk. There are a few different ways to create this pressure. For example, a layer of sand around 20 cm thick on top of the plastic; tyres, which exert an even pressure on the whole pit or bunk; straps that are pulled tight every 1 m to 1.50 m; or a system using heavy-duty plastic combined with large water hoses.
Taking the silage out of the pit or bunk
Once the silage has been harvested, packed and covered, fermentation will start. The sugars and the acids in the silage cause a lowering of the pH. This is the fermentation process. If the pit or bunk is airtight, this process stops at a certain moment. Most of the time, this takes around 6 weeks to 8 weeks.
After 6 weeks to 8 weeks, the fermentation process is complete and the pit or bunk can be opened to feed the silage to the cows.
If the pit or bunk is opened, the fermentation process starts again. It is important to keep the feeding speed of the silage in mind. A rule of thumb is 1.50 m per week. Do not open the pit or bunk too far, to prevent it heating up. This results in the silage no longer being tasty for the cows.