Making high quality silage

The quality of any silage crop is dependant on the pasture it is made from, the speed of wilting and the dry matter content achieved. Making quality silage depends on a number of important factors and good decision-making.             Silage should be harvested two to five weeks ahead of the time for haymaking, about 40 days after the last grazing and no later than the ten percent head stage to achieve a good compromise between quality and yield.             Digestibility, protein content and energy content decrease as harvesting is delayed. Pasture quality reaches its maximum about one week before seed head emergence. For each day delay in harvest the digestibility falls by 0.4 percent on average. For each one percent unit increase in digestibility for silage an additional 0.37kg of milk per day can be produced.             Wilting should be rapid (24-48 hours) to achieve at least 35 percent DM for pit silage and 45-50 percent dry matter content for baled silage to ensure high quality silage. Needless to say, avoid wet weather if possible. Leave the cut swath as wide as possible to promote fast wilting and use a tedder rake. especially if the drying conditions are poor. If rains come it is better to ensile grass that is a bit damp rather than waiting to dry it out again.             Once cut, it is critical to get the silage baled and wrapped or into a pit or stack and covered in a 24-48 hr period to maximise its digestibility. Mow as early as possible in the day when any dew is gone (this is more important to reducing quality losses than the argument that mowing should be in the late afternoon as sugar levels are higher then).             Harvesting and storage should be such that the fermentation, production of lactic acid and decrease to about pH 4 takes place rapidly and that air is quickly and permanently excluded to reduce mould growth and gas and effluent production.             Feed out management is very important to the overall cost of silage. In particular, significant losses (around 30-40 percent on average) can occur from poor management of the face of pit silage, leading to deterioration and spoilage. Damage to silage plastic or wrap should be prevented as much as possible and fixed immediately with bale tape.             Know your silage quality and its real cost taking into account all costs and losses and compare it with the cost of alternatives. Get a sample tested so you can assess your own or your contractor’s silage-making skills and so you know the feed value of the silage you are purchasing or have made on farm.