Silage Advisory Centre

Forage Matters spoke to him to find out more.

How do you prepare your soil?

An important part of treating grass silage as a crop is to get the soil preparation right, so we take soil samples and feed according to requirements.  We use about 80 units per acre of Nitrogen to fertilise, as well as slurry which we prefer to inject.  We carry out field analysis in autumn and correct P and K where required, applying more slurry and dirty water to fields which didn’t produce as well the previous year. 

What mix of forage crops do you rely on?

We use Italian ryegrass, but introduced red clover last year for the high protein levels it brings without needing extra Nitrogen.  This year we also over seeded our Italian ryegrass swards with red clover after the first cut, which is now starting to germinate – there wasn’t enough moisture earlier in the year.  We’re aiming for about 18% red clover in the grass as we think it dramatically improves eating quality.

What impact has introducing red clover had on production and other measures?

We’ve not had a long enough run to be able to give an annual overview but in four months of feeding last year’s silage as forage our calving index went down from 456 days to between 380 and 390 days.  Milk production improved by about two to three litres per cow per day and milk quality was very good for these high yields, running at an average of 4.3 butterfat and 3.5 protein.  When we returned to feeding grass silage made from old grass leys, the calving index went to 404 days and feed costs increased by £2,000 per month, as we had to re-introduce protected fat and extra protein into the diet.

Have you seen differences in digestibility and how important is this?

It’s important to choose specific silage crops which give the best return in terms of eating quality and digestibility - we’ve seen improvements in body condition, intake and milk production after varying the mix and introducing legumes. 

I’m now looking at introducing leys sown with a mix of Timothy grass and red clover.  The grass is more drought resistant with deeper roots than Italian ryegrass.  Its good level of coarseness will provide scratch factor and will be more digestible than straw.  I think it will deliver good protein levels, and we’ll probably preserve it in big bales, as it will be a very sweet smelling high dry matter forage that can be selectively in fed.

What yields are you getting?

We aim for five or six cuts during a year. By the end of July we had done four, even in this very poor grass growing year. Overall, we’re getting good yields. 

We only had four tonnes per acre with the first cut this year but it was a very cold, wet spring; seven to eight tonnes per acre with the second and by our third cut we’d ensiled an average of 16 tonnes per acre so far this year, more than some get annually. 

For me, quality is more important than yield, as quality equals digestibility which increases intake and productivity – that’s why it’s important to think carefully about the crop mix and to monitor its growth and maturity just as you would any other arable crop. We’re getting consistent quality on each cut of over 75 D-value and 12.0 M.E. silage.

The key is to treat the silage crop as you would any other, and keep a close eye on maturity levels – once the bottom two leaves have started to die, the crop won’t improve and it’s time to cut. 

What are your top three tips for generating good quality forage from silage?

1. Look carefully at the grass varieties and research different types – without the right crop you’ll never get decent forage even if you follow the best ensiling techniques.

2. Treat the silage crop as you would any other arable crop, and focus on crop maturity irrespective of yield.

3. Get any necessary fertiliser on the field within 24 to 48 hours of cutting.  Grass grows immediately after cutting if cut at the right stage, so you’re wasting that growth if you don’t make the most of it.

About Rodwell Farm:

• Working farm also used for training
• 400 acres, 300 ploughable
• Livestock: dairy, beef and sheep
• Arable: wheat, maize, Italian ryegrass and red clover
• Holstein dairy herd 230 heads – plans to reach 250 by end 2010
• 210 dairy heifers as replacements
• Milking average: 9,700 litres
• Grass silage covers 60% of forage requirements of mixed diet
• Other forages: maize and wholecrop wheat