Only now are we seeing grass beginning to grow and the colour return to the countryside as temperatures rise.

It will be the silage season next, when we look to produce next year’s winter forage. The aim is simple — to cut growing grass at its nutritional peak and conserve it with the minimum amount of losses.

This spring has seen a number of factors which could produce problems in 2010. The cold weather in February and March meant a lot of slurry was applied, with little or no uptake by plants.

Wet weather over Easter also meant the late application of a lot of fertiliser. So, at the end of April and early May, grass growth will be very fast, sucking up all surplus nutrients.

We all work on an average figure of two units a day for nitrogen use, but this can vary from 1 to 5 units a day. With such a fast growing season for first cut there could be problems.

Excess nitrogen in silages makes it harder to ferment, and in extreme cases leads to very butyric silages.

Don’t forget second cuts either. Slurry which has been slowly taken up doesn’t always affect first cut, but loads up the second cut instead. Silage is the cornerstone to profitability and with that in mind these are a few pointers for successful silage making: 1. Preparation. Clean out silos and ensure all effluent channels and tanks are ready for their purpose. Clamp construction should be double checked to ensure walls are sound and that sleepers and panels are fit for their purpose.

2. Test the grass sugar and nitrate levels. A lot is talked about sugar levels, but the advice is simple, as a rule of thumb levels should be above 3% in fresh grass, to fuel fermentation. Check for high nitrates caused by residual slurry or unused fertiliser, as this can really increase that 3% requirement. Tests usually take 24 hours, and should be done a few days before cutting. CCF can arrange this. Too many types of silage are ruined every year by not doing a pre cut test, especially considering the conditions this spring.

3. Mow high, leaving a minimum of three inches stubble, to avoid scalping and soil contamination, and encourage quick regrowths. It also aids clean raking by holding the crop off the deck, 4. Wilt quickly if conditions allow, ideally up to 28-30% dry matter. Wilting can reduce or eliminate effluent production. Mechanical aids like conditioners and tedders can be used to speed up the wilting rate, but don’t wilt for more than 24 hours, as after this grass will begin to respire and starts to deteriorate.

5. Fill the clamp evenly, ensuring air is expelled at all stages. An extra tractor rolling is always beneficial when keeping up with modern machinery work rates.

6. Sheet well, always using side sheets, and consider using at least two sheets on top. Clamp film is a new, clear cling film like product that is gaining in popularity and has been shown to reduce surface waste and ensure an air tight seal. Remember also to weigh down right across the sheet surface, with either touching tyres or mats. Secure covers work well, but these still require sufficient gravel bags to weight down edges and seams.

7. Use an effective additive. Silage additives come in many shapes and forms, and in many cases these products are backed up by years of trial work. Put simply, five pence a day per cow spent on additive can yield up to and beyond an extra litre of milk which, at 20 pence, is a 3:1 return. It’s seems like a no brainer, but look for evidence to support claims. Products with a 1million effective bacteria have been shown to have a positive effect on fermentation and animal performance. The best silages contain more nutrients, and treating them to drop pH levels quickly, has been shown to retain more effective protein and carbohydrate for animal performance. Next winter’s good milk yields always come from what we do in May, six months earlier.

8. Leave the clamp alone. In an ideal situation silages need at least four to six weeks to fully ferment. During that time an air tight seal is required, so always check for signs of slack sheets as some clamps sink, adjust cover weights to keep the sheets tight. Failure to due this will lead to surface waste and increased fermentation losses.