Silage is pasture grass that has been ‘pickled’. It is a method used to preserve the pasture for cows and sheep to eat later when natural pasture isn’t good, like in the dry season.

The grasses are cut and then fermented to keep as much of the nutrients (such as sugars and proteins) as possible. The fermentation is carried out by microscopic organisms living in the grass.

The process must be carried out under acidic conditions (around pH 4-5) in order to keep nutrients and provide a form of food that cows and sheep will like to eat. Fermentation at higher pH results in silage that has a bad taste, and lower amounts of sugars and proteins.

Silage bales in plastic

The plastic is used to create an anaerobic atmosphere inside the bale. This is needed for the pasture to ferment.

How is silage made?
Preparing the grass

First, the pasture must be cut when the grasses contain their highest nutrient levels. This is usually just before they are fully mature. This is important because all forms of preserved grass, such as hay and silage, will have lower amounts of nutrients than fresh pasture, so everything must be done to make the end product be as nutritious as possible.

Grass is allowed to wilt in the field for a few hours to reduce the moisture content to around 60-75%. This moisture level will allow for optimum fermentation. If the grass is left out longer, it may get too dry, or it may get rained on – and both these will reduce proper fermentation. Also, the longer the grass is left uncut, the higher the loss of nutrients.
Fermentation

The cut grass is chopped into even smaller pieces and then compacted to get out as much oxygen as possible (this is important because the microorganisms, called lactic acid bacteria, that are needed to carry out the fermentation like living in oxygen-free environments). For this and many more full episodes at https://youtube.com/@farmwithmilly?si=ekYNgf7g5FpSiEIG SUBSCRIBE!