Expert panel - how conditions have effected forage

We've asked industry experts to give us their views on how the wet growing season last year and the cold weather this spring have effected forage and what  you need to be thinking about this season.

John Morgan, Maize Growers Association

It is generally accepted that soil temperatures need to consistently hit 8°C at 9a.m.  in order that maize seeds germinate where plastic is not used, and 6°C where  plastic film is laid over the sown maize seeds.

With soil temperature data taken from growers around the country and made available to all via the MGA website, showing that 6°C has now been reached, maize under plastic is being drilled, perhaps a week to ten days later than last year.

Soils are only just warm enough for conventional maize establishment and growers should get on with seedbed establishment now even if they hold back on actually drilling until things warm up a little.

On average I suspect that maize drilling will be ten days later on average than last year when we look back at the spring.

Early drilling gives the maize plant the best opportunity to make the most of the relatively long days and will almost definitely result in an earlier harvest this autumn.

Early harvest will allow farmers to get much needed maize back into rations, better establish following crops and equally importantly reduce the likelihood of soil compaction related issues associated with soil erosion and soil wash.

All that said, there is a risk that like last year the season turns bad again with the result that seedbeds get colder and seeds rather than germinate simply rot in the ground. The chances of this happening must surely be low so the recommendation from the MGA still stands.

Drill when soil temperatures hit 8 degrees for five days in the trot, when soil conditions are good and the short term weather forecast looks favourable

 

Chris Duller, independent soil and grassland management specialist

Ryegrass is wonderful stuff - but we have to remember that it doesn't like difficult conditions. Limit its resources, either through a shortage of nutrients or by restricting its rooting capacity and ryegrass will struggle and ultimately disappear from a sward, and is likely to be replaced with poorer performing weed grasses.

Last year's wet conditions led to soils being damaged, mainly through compaction in the top few inches by grazing cattle or silage traffic. For many, this compaction damage has been compounded by slurry applications in wet conditions and the net result is a tight soil structure, poor water movement, limited root growth and a shortage of earthworm activity.

In a warmer spring the natural recovery process would have started weeks ago - as soils dry they crack and lift, new earthworms hatch from eggs produced last summer and fresh root growth starts to move into and break up any large soil aggregates. That simply hasn't happened yet.

As we approach peak grass growth over the next few weeks we need to think about helping the recovery process in some way - otherwise swards
are likely to go backwards fairly quickly.

Dig and look - identify fields where soils are compacted, root growth limited and worm activity poor and prioritise these for a bit of TLC.

The main objective is avoid any more damage - no grazing or traffic in wet conditions. This may mean compromising your grazing or silage targets, for example grazing a paddock early before it reaches its ideal entry cover. Grazing a low cover, with a low stocking rate on a dry day is far better than tight stocking a 3000+kg DM/ha cover on a wet day.

If weather and ground conditions are poor at silage time - leave a damaged field to bale later in better conditions, it may lose quality - but at least you've given soils a chance to recover.

To speed up the recovery process and get some air back in your soils there is theoption of either soil aeration or sward lifting. These operations are normally best left until after peak grass growth as they will damage roots and you'll see a yield penalty - autumn is best.

But if soils are really struggling it may be best to sacrifice grass growth for an opportunity to run this type of machine in 'ideal ' working conditions - otherwise you could enter another wet autumn and winter with nothing having been done.


Piers Badnell, DairyCo extension officer and technical specialist

The coldest spring in 50 years and the wettest for 100 years last year means the vast majority of farms have completely exhausted silage stocks and have been buying it in or are very nearly out. The insurance that has been at the back of the clamp has gone or is virtually gone.

Not many can remember a year that has been so difficult, so what can we do to replenish stocks in what is now a shortened growing season due to the cold start?

How much you want to put in the clamp for insurance depends a bit on your view on risk.

  • For those that are risk averse I have heard one producer say he is not ever going to be without nine months in the pit above
    what he needs
  • The other end of the scale is the belief that it is once in 50 years occurrence, it won't happen in my working lifetime again so I have taken the hit this year but I'm not changing my policy of finishing the pit each year. Silage costs me £35/t to produce so if I have 500 - 1000 tonnes in stock as a carry over for insurance that is very expensive

For most producers the view of the risk of bad weather will lie somewhere in between those above but we do need to bear in mind that our climate is changing, and we are more likely to see extreme weather patterns in the future.

So how are we going to replenish stocks and have enough forage for next winter?

I think there are signs that next winter could be expensive:

We have low forage stocks, if any, and the season has been very slow to get going

Cereal crops look average at best - there has been a lot of late spring barley drilled but it is very unlikely to produce bumper yields so I think there maybe pressure on prices

What are we going to do to get good quality stocks of forage so we are not so dependent on bought in concentrate?

  • First things first, soils. This is where it all starts so make sure you have the correct pH P&K indices and your soils are not compacted, without getting this sorted you will reduce potential growth and thus yields
  • In terms of grazing work the grass hard. Graze hard, achieve your target residuals, and when a paddock has got above 3000kg DM/ha get it cut and baled so that you have that grass growing again as soon as possible. Measuring with a plate meter and /or using the 3 leaf method are essential
  • Reduce waste at silage time. Careful attention to detail when mowing and lifting in the field and, good consolidation in the pit (no more than 25cm/layer) will help reduce any wastage. Covering the pit at night, can also help minimise spoilage
  • If you have excellent procedures you will lose 15% from cutting to feeding out from work that Raymond Jones did at IGER but that loss can be as high as 45% through bad practice.
  • Because of the cold spring do a pre cut grass test on your silage grass a couple of days before you intend to cut, to check for ammonium-N levels. As it has been an odd spring these maybe higher than you expect don't get caught out.
  • It is also a good time to check sulphur levels to aid you in fertiliser policy for second cut
  • Look to fertiliser policy to get the return. Regular 21 day applications of nitrogen on grazing to get the growth. Response to nitrogen is good and it pays as long as you utilise the grass grown
  • Very good advice can be found in RB209 which can be downloaded from the DEFRA website
  • If you are short on forage another option maybe to select an underperforming field or a cereal field that is patchy and sparse, and redrill with Italian ryegrass now. This would be ready for cutting at the end of June and in its first year IRG just grows and grows so there is potential for good output and a pit filler
  • Be flexible and take opportunities when they come. Cutting silage 4-5 times over the season may help bulk up stocks and this should be good quality forage. This is not a normal recommendation but then for many this is not a normal year and sometimes that means looking at things in a different way.

Assess your needs and act accordingly

  • During the season assess how much forage you will need and how you are doing against that requirement. If you are coming short look to take out unproductive animals. Cull prices are good at the moment don't leave the decision to crunch time when others maybe doing the same and prices might fall. Take the money and reduce your forage demand earlier rather than late
  • Another alternative is to defer grazing later in the season to use through the autumn and into the winter to reduce silage demand and reducing housing costs. Remember  straw maybe tight as a result of poorer cereal crops
  • Look at the possibilities of out wintering stock to reduce your requirement for silage and straw. Talk to someone who has done it and find out the good, bad and indifferent
  • We will cover out wintering and deferred grazing in later Forage for Knowledge articles.