5 tips for growing good quality silage: silage season done right
One of the most expensive days in the Irish farming calendar is when the silage contractor rolls into the yard. Rising costs mean that this very important day is now more significant than ever. Farmers must ensure that the highest quality silage is made for the winter months ahead, especially as purchased feed prices continue to soar.
Read on to find out more about the importance of good quality silage, 5 top tips on growing silage, and how IAS can help.
The importance of good quality silage
Silage, which consists of grass or other green fodder, can contribute up to 6 months of an animal’s annual feed. It is critically important to take steps to produce the best quality silage now, consistent with high yields, as poor silage will result in buying more expensive rations this winter.
Silage quality has a considerable impact on nutrient and dry matter digestibility (DMD) in livestock. This leads to improved productivity, which in turn increases profitability and helps mitigate rising costs. Superior DMD means that the silage is easier to digest, making the nutrients more available to the animal. This reduces the likelihood of nutrition-related diseases as well as the need for supplements down the road.
Growing good quality silage: 5 top tips
- Avoid soil contamination
Research shows that the feeding value of silage will be linked to the quality of the grass and the steps taken during mowing, wilting, and preserving. For a start, it is important to avoid soil contamination of the silage, which can result in poor preservation and reduced feed quality. When a contractor comes to the farm to pick up grass in the field for the silage process, they should pay close attention to detail and follow good work practices to prevent clipping the top off the surface and any soil being taken up along with the grass.
When testing silage in November, laboratories often ask if there was any soil contamination, as this can affect nutritional results. Contamination will also play a huge part at the end of the year. It often means that the silage is unpalatable for the animals, meaning they are less likely to consume it and more likely to require supplementary feed.
- Ensure optimal sugar and nitrate levels (with laboratory analysis)
Two of the most important factors in getting a good preservation in silage are the sugar and nitrate levels in the grass at ensiling. Farmers should target a high sugar content and low nitrogen content for harvesting.
It is recommended that grass should have sugar levels of 3% or higher and nitrogen levels lower than 300ppm (300mg/l NO3). Not enough sugar means that the grass will not save and therefore unable to be used effectively for silage. Sugar levels can be up to 50pc higher in ryegrasses than old pasture grasses.
Whilst sugar levels are also somewhat weather dependent (see tip 3 for more details), nitrogen can be more easily influenced. As a rule of thumb, grass uses 2 units of nitrogen per day as it grows. So, if you apply 100 units of nitrogen fertiliser per acre, it will take 50 days on average for it to be used up. However, there are no hard and fast rules around this, so testing is vital to confirm that nitrogen levels are optimal for ensiling.
This combination ensures good silage preservation, higher intake potential, and improved animal performance.
- Take notice of the weather
The unpredictable Irish weather plays a major role on the ensilability of a crop. Sunny weather in the weeks leading up to cutting will help to increase its sugar content. While this is a factor we cannot predict or alter, taking our other tips into consideration (particularly tip 5) will help to mitigate any elements outside our control to ensure your silage is at the best possible level to cut for a quality feed this winter.
- Cut grass at optimal times
Cutting conditions and the time you choose to cut will have the greatest impact on sugar content in grass. It is best to cut early afternoon when both the sugars and dry matter levels of the grass are at their peak, as long as the grass is dry. If you bale silage that is too wet and runny, it will go bad and can be toxic to animals.
The crop will benefit if allowed to wilt for 24 hours in the sunshine before picking up. This process makes sure everything is stabilised for high quality silage.
The time of year silage is cut has an impact on the DMD. Silage cut in May will have the highest DMD, as later on the crop will begin to bulk up and produce stems and heads, decreasing digestibility. However, this is possibly the most difficult time to find optimal ensiling conditions. Silage DMD drops by roughly 3% from early May as growth can happen very quickly due to seasonal temperature increases, so the difficulty lies in striking a balance between quantity and quality of silage.
- Take the guesswork away with IAS Laboratories’ analytical services
The goal with silage is to cut early enough in May to maximise DMD, but also to cut when sugars and nitrates are in the desired ranges to ensure good preservation. However, farmers are often at the mercy of the weather, the seasons, and unpredictable markets.
IAS Laboratories offers a pre-cut silage test, which determines sugar and nitrate levels in the crop. Testing your grass before cutting is the only way to be certain you are within the necessary parameters for good quality silage.
This is more important than ever before in our current climate of expensive fertilisers and animal feed. Accurate and insightful results reveal data that will allow farmers and advisors to take corrective action in time to have a direct effect on silage quality. This will save money in the long run, as they will not need to buy supplementary feed later in the year to keep animals productive.
For more information on our agricultural services or to book your test kit now, visit our website. We provide results on the same day if samples are received before 10am.