The wet spring has provided ideal conditions for Light Leaf Spot (LLS) to flourish in winter oilseed rape crops as the disease is spread by rain splashes, and as LLS comes into the crop from November onwards, it requires treatment into the spring months. However this year some growers may have missed their autumn sprays, normally targeted against phoma but have an effect against LLS, or it was so wet that they could not travel.

The implications of these high infection levels for next season’s crops are considerable, as the fungus which causes LLS can continue to cycle in the crop for the whole season providing that weather conditions are conducive. The fungus survives on debris after harvest and then is ready to infect nearby crops emerging in the autumn.

Growers are urged to consider the role that genetics can play in helping to defend against the disease which is equated to the ’septoria tritici of oilseed rape’ and which experts believe costs growers £140m a year in lost yields.

“Left unchecked LLS can depress yield by more than 1t/ha. Fungicides, of course, can play an important role in controlling the disease but inherent, genetic resistance will give an underlying protection that is invaluable when weather conditions are not favourable to spraying the crop, or the disease is not spotted,” says Agrii’s technical seed manager, David Leaper. 

“Last year we didn’t see such an impact on yield from LLS in England in spite of seeing significant disease in crops in early spring. Last year February and March were cold and dry, so leaves tended to drop off and the levels of infection were reduced. This year with the cold, wet spring, plants have held onto their leaves and it has been easier to see the symptoms develop and get progressively worse.”

ADAS’ plant pathology researcher, Julie Smith agrees. “We have seen big yield losses from LLS in recent year’s particularly when fields have been too wet to travel and fungicide timings have slipped. Even the strongest products will not perform well in highly curative situations so it’s important not to let the disease become established early on.”

“As a rule of thumb, 15% plants affected at stem extension equates to a 5% yield loss and I saw commercial crops in the spring which were close to 50% affected. LLS will cycle approximately every 4-6 weeks and the wet weather has helped splash spores around and enabled the fungus to progress up the canopy. “

“In some years we only see disease in the lower – mid third of the plant but I have seen several crops this season with actively sporulating lesions on upper leaves. These crops are particularly at risk of LLS reaching the pods, which, once infected are likely to senesce prematurely and shatter, causing significant seed losses.”

“I have also had calls from concerned growers reporting LLS infection on the buds which has subsequently affected flowering. “

With conditions this winter and spring being so suited to the spread of the disease, Mr Leaper expected to see high infections of LLS across the Agrii WOSR national trials sites but in fact levels are much higher than he expected.

“You would expect levels of infection to be high in the north and they are, and we know that LLS has been spreading further and further south and west, but it’s alarming to see just how high the levels of LLS are at both the Kent site and the Agrifocus site in Swindon.”

“We have five key trials sites; Cambridgeshire, East Yorkshire, Perth & Kinross, our Agriifocus site in Wiltshire to Kent, at which we have plots of all of the main commercial and candidate OSR varieties.”

“In our trials we have included a wide range of conventional, hybrid and HOLL recommended and candidate varieties, with up to 40 varieties in the ground, which allows us to really pull apart how the resistance ratings are standing up to the current pressure, but also to see if we future varieties are going to offer any more than what we already have, “he adds.

“We conduct both untreated and treated comparisons, however, it’s important to note that the fungicide regime that we use on the treated plots is more similar to that of a farm level programme, so we do see different results to the AHDB trials that receive a fully comprehensive fungicide programme. “

Mr Leaper explains that at the end of March into early April plots across all of the sites were scored for LLS infection on a rating of 1-9 (with 1 being no infection and 9 being severe) and an average across the sites has then been taken for each variety.

“The results have been alarming as there were only four varieties that showed up to or less than 2.5 % infection; the conventional variety Nikita stands out with one of the lowest infection levels at 2.3%, taking into account both treated and untreated results.

“Looking at this in more detail, at both the Agrifocus and Kent treated sites, only 1% of plants were infected, and this only went up to 3% of plants infected on the untreated plots, clearly demonstrating the robustness of Nikita’s 7 for LLS resistance.”

“Interestingly, varieties with a resistance rating just one lower than Nikita’s did not perform nearly as well. For example, Campus which is rated a 6 for LLS on the RL showed 6% infection in the untreated and 5% in the treated.”

“None of the candidate varieties offered any better results than current recommended varieties, so there is no new shining star coming through in the immediate future that will offer better resistance to what we currently have.“

Nikita missed out being recommended for the east/west list last year on the basis of its lower phoma rating. While this was disappointing we know that in an open autumn a vigorous variety like Nikita will grow quickly. The likelihood of phoma developing into the yield robbing phase of the disease, stem canker, is much reduced says Mr Leaper.

“With current LLS pressure this disease must take precedence as it is a much more progressive disease and more difficult to control with the sprayer. Having robust LLS resistance is crucial

“It’s certainly worth considering this wherever you are in the country when planning variety choice for next year as infection levels look high and autumn conditions are always uncertain for spraying.”.

Dr Vasilis Gegas, senior oilseed rape breeder with Limagrain, notes that in years when LLS pressure is high, resistance ratings may come under pressure and therefore there’s a distinct advantage in starting with the highest rating possible.

“There have been considerable advances in varietal defence to LLS in the last five years and one of the reasons for this comes down to the fact that with increasing levels of infection year on year, breeders have been able to make better selections and that is why we are seeing varieties with better LLS resistance. “

Data from CropMonitor show that LLS is increasing year on year on a national scale so we are not yet winning the battle adds Miss Smith. “We need to make smarter variety choices and integrate fungicide programmes with varietal resistance. We have had limited options on the east –west RL list because most of the varieties have been susceptible to LLS with resistance ratings of 6 or below but things are changing now. There are some excellent new varieties coming through and we must start using them if we are to achieve robust disease control whilst minimising the drive toward fungicide insensitivity.”

This is a new role within the company that reflects the ever increasing need for technical support for its extensive range of varieties for the arable market.
Jessica recently graduated from Newcastle University where she studied Agribusiness Management, however it was her summer job working with the Limagrain barley team that piqued her interest in plant breeding. 

“I worked with the barley breeding team last summer and had the absolute time of my life! I was the first student to start and the last to leave. Starting so early meant I got to disease score with our cereal pathologist, giving me a great insight into the agronomy side of things.”

“It was during these field outings that I met Ron Granger, the technical manager, he offered kind words and encouraged me to pursue a career in agriculture.”

“This is a really exciting time for plant breeding as new and exciting high yielding and disease resistant varieties are being developed, and I am really delighted to be involved in bringing these varieties to market.”

Many varieties do not make the AHDB Recommended List (RL) based purely on their yield, however they often offer valuable agronomic traits and it is worth considering these when making decisions for this autumn, what is on offer depending on what the particular issue is, he says.

Jim continues; “In the north for a variety to be successful it must offer good early vigour and autumn development in order to have the best chance of establishing strongly, resisting early pest and disease damage, and growing reliably away from the winter under increasingly variable and challenging climatic conditions.” 

“This early growth habit can be influenced by seed rate, soil fertility and sowing time, but it’s largely genetic, allowing varieties to be selected to make the most of different conditions.”

“In our trials and demonstration sites throughout the north of England and Scotland, we look at a range of varieties that are both on and off the RL, and measure these for relevant attributes.”

For the coming season, we are particularly impressed with the hybrid variety, Archimedes from Limagrain UK that is not only clubroot resistant, but has demonstrated excellent agronomic characteristics that suit northern growing conditions.”

“Archimedes has been particularly impressive in terms of its vigour; in our trials it has shown itself to be a variety that gets up and away quickly – much more so than the Recommended Lists clubroot variety, Mentor. Mentor can struggle a bit in terms of establishment in the more challenging conditions up north, unless sown early.”

Senior OSR breeder at Limagrain Dr Vasilis Gegas, explains that Archimedes has completed National List trials, but has a slightly lower gross output to similar varieties which is why it is not on the RL. However he points out that whilst some varieties, such as Mentor, may have a higher gross output on paper, it is not going to reach its potential if it doesn’t establish well in the autumn.
Mr Carswell agrees and underlines the need for a good set of agronomics to support the variety. “Up north we need earlier flowering and maturing varieties, attributes which Archimedes offers and the variety also has pod shatter resistance; an important attribute for securing full yield potential.”

“Archimedes has robust disease resistance ratings valued by northern growers, offering a 6 for Light Leaf Spot and an impressive 8 for stem canker.”
Archimedes is a medium-tall variety with good lodging resistance and stem stiffness.

Agronomic Performance Data

January 2016. Data from the AHDB NL2 Candidate report – North 2-year summary 2014/15 data. *Mentor and *Cracker data from the Recommended Lists database 2016/17, North Region. On the 1-9 scales, high figures indicate that a variety shows the character to a high degree. Clubroot varieties have specific resistance to clubroot which is efficient in most cases but does not guarantee 100% resistance in situations of evolving strains.

Dr Gegas reminds growers of the importance of selecting a clubroot resistant variety in those regions that clubroot severity is expected to be high.

“Closer rotations of OSR crops and brassicas, warm and wet winters, and flooding all lead to higher incidences of the clubroot pathogen, and the effects of infection should not be underestimated, as crops infected – even if not showing symptoms – will result in a yield penalty.”

“Yields can be affected even at low incidence of the pathogen, and severe cases can lead to secondary rot of the roots, or even total plant loss.”

“It’s important however to adopt a management strategy that includes wider rotations (at least 5 years between Brassicas) and close monitoring of risk factors (soil pH, calcium levels, drainage, cross-contamination) – to avoid over-reliance on resistant varieties,” he says.

“Dairy, sheep and beef producers could see some real benefits from growing this leafy catch crop,” says Limagrain UK’s forage crop manager Martin Titley. “It has a flexible sowing period, from May until the end of August, and is sown either by direct drilling or broadcasting seed. And only minimal cultivation is needed after cereals, making it one of the cheaper forage crops to grow.

“Forage rape can also be mixed with grass seed for an autumn reseed and the sward can be grazed while the young grass seedlings establish underneath making for a productive sward that much sooner.”

He points out that one of the greatest benefits of this crop is its versatility when it comes to feeding. “Not only does it grow quickly, but it can fill the forage gap through autumn and winter and can be utilised when you need it”

According to Kingshay figures, forage rape costs £408 per hectare to grow, making it one of the cheaper forage crop options. “But the crop will reliably yield 30 tonnes of fresh feed per hectare,” adds Mr Titley. “And based on our field trials, that include 12 years’ worth of consecutive yield data, the crude protein content of forage rape and its hybrids is among the best of any forage crop at 19% to 20%. It has an energy value of 10 to 11MJ/kg DM.

Sowing forage rape with stubble turnips is also very popular – and this will also add to the crop’s winter hardiness, and keep the stubble turnips protected from frost damage.  The variety Hobson is used very successfully here for finishing lambs as it is very palatable and highly resistant to powdery mildew.”

If the crop is required for autumn and winter feeding for dairy and sheep then the fast growing hybrid variety Interval is highly popular. It establishes very quickly and has dry matter yield 10% higher than the control variety in Limagrain UK’s trials, and again is highly resistant to powdery mildew.

“Forage rape and rape kale hybrids will also grow in poorer soils and on exposed sites too,” adds Mr Titley. “In fact, most crops can make a valuable contribution to the supply of home grown forages.”

Positioned in the surrounding countryside of Shropshire; lies Market Drayton Golf Club which was established in 1906. This challenging 18 hole parkland course offers spectacular views and also supports a rich variety of wildlife.
Regarded as one of the best golf courses in the county, Simon and his three full time members of staff and one part time, are tasked with maintaining the course at Market Drayton Golf Club to the highest possible standard.

Simon has been an employee at the club for over twenty-five years and for twenty of those years he has been using Limagrain products. In 2010 he decided to undertake a major greens renovation programme and to help him along the way he sought the advice of the company.

“Between 2008 and 2010 we made some improvements to the greens which resulted in better drainage and surfaces. Because we had drier greens we thought that we would try and get rid of the meadow grasses so we started taking advice from Limagrain on how to take meadow grass greens over to bent grass greens. They have been great and have been helping me with a number of things including varieties, planting regimes, overseeding and getting the best out of the Graden machine initially and later a sorrel roller type speed seed.”

To improve the overall quality of the grass species, Simon overseeds with Limagrain’s MM9 grass seed, which is a product of the MM range – one of the most respected brands in the UK amenity industry. The MM9 grass seed produces a fine, dense sward for the ultimate playing surface, and Simon has certainly noticed the improvements.

“From 2010 until 2013 we overseeded just once a year with the MM9 and were putting on 5g per square metre through the Graden. In 2014 we started using 2g a month in May, June, July and August with an overseeder and we did the same this year.

“MM9 has extremely quick germination and we’ve seen a massive increase in grass coverage and density in the last five years on the greens. We now have greens dominated by up to 70% bent grass instead of annual meadow grass.

 “It’s safe to say that I would absolutely recommend Limagrain.”

For further information, please contact Limagrain UK on 01472 371471 or visit the company’s website www.limagrain.co.uk/amenity. You can also follow the company on Twitter: @MM_Seed

MM9 before renovation

MM9 after renovation

This season is no different, as growers should be patient and delay drilling, until good seed beds with warming soil temperatures ensure quick plant establishment – spring growing crops do not like growth checks.

“We have carried out trials, looking at variety interaction with seed rate for two consecutive seasons in both Scotland and Norfolk. These two seasons were very different with regards to establishment and disease pressure –however despite this a rate of 350 seeds/m² would still appear to be correct.”

“Although we saw a slight increase in yield in the 2015 data sets, especially for the newer varieties with an increased seed rate, in general over two years the 350 seeds/m²  rate would appear to be the most cost-effective.”

However he points out that seed rates for spring barley, as for many cereal crops is not an exact science and will need adjusting depending on drilling date, tillering capacity, soil conditions, weather forecast, pest activity and most importantly growers knowledge from previous experience.

Specific weight

“Specific weight however would not appear to be greatly influenced by differing seed rates, but in general the standard 350 seeds/m² in the 2014 and 2015 season, produced the best specific weight for the majority of the varieties in the trial.”

“In general the drive for higher yield has driven varieties towards a later maturity and it is also quite evident that these varieties would also appear to have lower specific weight recordings as compared with past older varieties – but Sienna bucks the trend -and has the best specific weight on the AHDB Recommended List.”

“It’s necessary to keep testing these new high yielding lines to ensure that historic agronomic inputs are still relevant in today’s climate, especially when we know that many of the  new spring barley varieties have significantly increased yield potential over the last six years.

“Limagrain has been monitoring the tillering capacity of spring barley lines over many years, and it is quite evident that many of the newer varieties appear to be producing higher tiller counts.

For example, Concerto is known to be a lower tillering variety and as such is lower yielding than the newer higher tillering varieties from Limagrain such as Octavia, Olympus and Sienna. “

“Looking at tiller counts versus yield from trials, our analysis would confer that higher tiller counts are increasing yield potential; for full yield potential we should be aiming at a final tiller count of 775 – 800 /m² in line with the AHDB Barley growth guide recommendations.”

“Spring barley varieties with higher tiller counts are desirable, as in challenging periods during the spring, these varieties are able to lose tillers without a significant yield penalty whereas  low tillering varieties will struggle to compensate when the environment is not favourable, due to a loss of tillers.”

Tiller counts

Managing tillering with inputs

Limagrain trials data shows that an additional application of nitrogen can be helpful if plant counts and tiller numbers are low, to increase both tiller number and more importantly tiller survival.

“The data from our on-going Scottish trials suggests that the standard nitrogen application rate of 120 – 150kg/ha is the optimum requirement for yield versus grain nitrogen content, “ says Mr Granger.

“With regards to the south of England, our data is more limited, but it is clear that nitrogen rates may have to be increased especially on the better soil types with higher tiller number potential, to ensure both full yield potential and grain nitrogen content are achieved.”

Mr Granger points out that growers need to know what market they are aiming for regarding the choice of spring barley variety as pushing for yield has to be weighed up with the grain nitrogen content requirement requested by the end user .

“In addition to nitrogen, applications of sulphur and manganese are very beneficial in the early stages of plant growth in spring barley,” he adds.

Nitrogen / Fungicide Vs  Yield interaction

Fungicide programmes need to be flexible depending on disease pressure during the growing season, he says.

“As you can see in 2015 in what was a low disease pressure year, the fungicide programmes was reduced accordingly. In comparison, 2014 was a high disease pressure season and the higher rate fungicide programme had the advantage.”

“In either situation accurate timing of the application of chemistry used was key to maintaining healthy plant development for full yield potential.”

“Our system is based around feeding a consistent diet from the start of the transition period right through until cows are confirmed in calf,” Jon explains.  “We want to avoid any changes which might upset the rumen and affect overall performance.  So we need a maize variety that not only yields well but also gives a flexible harvest window, because we are right on the coast which is a far from ideal growing area.”

The cows are predominantly Holsteins but they have been cross bred with Norwegian Reds, Flekvieh and some Montbeliardes.  Calving is in a tight 12 week block starting in early September with heifers calving at the start of the block.

“Cows are housed three weeks pre-calving and stay housed until the spring.  Turning fresh calvers out to grass would make managing the diet and intakes a real challenge, potentially compromising peak yields and fertility.  We find it is much more effective to house them pre-calving, get them settled on the diet and then keep everything as consistent as possible.”

The cows are TMR fed with the diet put out once a day but pushed up regularly.  The diet normally comprises 60% maize silage, 40% grass silage, chopped straw, fodder beet, Home and Dry treated home grown barley, a 25% protein blend, fat, minerals and chopped straw.  In addition, cows will be fed 3-4kg/day of dairy cake in the parlour.

Cows will be turned out by day in February and the parlour cake will be changed to a 16% HDF.  They will be fed a buffer incorporating maize until a grazing wedge is established in April.  The feeder wagon is then turned off until August.

“Block calving means we can make full use of grazing as cows are mostly in calf by the time they go out.  It has also allowed us to reduce maize acreage.

“Previously we would grow 110 acres for 220 cows, but can now produce enough for the 300 cows from 90 acres.  However, we need to ensure the best possible quality performance from the smaller maize area so variety choice is key.”

Jon has been growing maize for 14 years and has used a number of varieties. For the last two years, following discussions with Alan Moore from ACT he has grown the LG variety Glory exclusively,.

“We look to balance a number of criteria when deciding on a variety,” Alan Moore explains.  “Given the location we need to choose an early variety, especially as the aim is to get a grass reseed or cereals in after maize.  We also want a flexible harvest window so we can get it off in good conditions.

“As far as feed value is concern, we want a high yielding variety with good starch content.  Maize is a feed and the quality of the feed we can produce is essential.  To grow an early variety you used to have to be prepared to sacrifice some yield and starch, but this is not the case now.

“Two years ago we tried Glory as it meets all our criteria, being maturity class 10 and scoring 7.5 for early vigour, combined with high starch content and excellent fibre digestibility.  It is the top ranked variety for starch yield and produces high dry matter yields.  It is 4^th highest on the BSPB/NIAB List for ME yield.  It has performed so well, we have moved away from growing a mix of varieties to growing just the one.”

 

While some of the 90 acres were sown on 10^th May, the majority went in on 25^th and 26^th May after first cut had been taken.  Jon says the sowing date had little impact on harvest date with some late sown fields ready first.  He believes field conditions, particularly shelter in his case, have far more influence on crop maturity.

Harvest this year was staggered as Jon was running low on maize carried over from 2014 and was going to be short for fresh calved and transition cows.  Ten acres was harvested on 1^st October, yielding around 150 tonnes at 31%DM, 10.8ME and 34.7% starch.

“The harvest window for Glory gave us the opportunity to take some early,” Jon Rogers continues.  “We could actually have taken the entire crop at this stage,
but hadn’t finished concreting the clamp.  The early harvest allowed us to have sufficient for immediate needs and meant the main harvested block could have at least four weeks in the clamp before being used, which is the minimum we aim for.”

In total the 90 acres yielded 1600 tonnes and Jon is confident he will have around 300 tonnes available to feed next autumn.  To help preserve quality and reduce heating the crop is treated with Safesile to limit aerobic spoilage.

“Having grown a quality feed it is important to minimise waste.  Even though we feed once a day we are getting virtually zero waste in the troughs and the diet doesn’t heat up during the day.

“We are averaging 27 litres per cow with 4.3% fat and 3.4% protein.  Rolling yield per cow is around 8,200 litres which I am happy with from cross-bred cows.  Fertility is generally good too, with around a 22% pregnancy rate and a 90% submission rate which I think reflects the system and ensuring a consistent diet with a healthy rumen using quality maize.”

“These results, that have been produced annually for the past 10 years, are increasingly important as our livestock producers look to maximise feed quality from home grown forages,” says Limagrain’s forage crop manager Martin Titley. “They can see the advantages in using the latest varieties that, for the same growing costs, offer agronomic benefits and improved feed quality.”

The trial results also include results specific to the crop and identify advantages of certain varieties over others. “For example, it’s important to highlight the percent of the root that is in the ground and the dirt tare in fodder beet varieties. And in the case of stubble turnips, growers need to know the relative disease resistance of each variety. The leaf to stem ratio is important in kale varieties too.”

He encourages livestock producers to take advantage of the information that is available free of charge from Limagrain or directly off the web site. “Fodder beet costs £1460 a hectare to grow but there is 14% difference in dry matter yield between the worst performing variety and the new variety Tarine,” adds Mr Titley. The digestibility values in kale varieties vary by 5.5% and the best performing swede variety Gowrie has a dry matter yield 18% above the control variety. So it is worth referring to the data and making wise choices based on UK trial data”

Limagrain’s latest Forage Crops Trial Results Guide for 2016 includes data for nine different forage crop species, to suit different land types, nutritional requirements and management systems. The booklet is available from Emily Short on 01472 370117 or emily.short@limagrain.co.uk or by downloading a copy from www.lgseeds.co.uk/tarine

All three varieties, that have been developed exclusively for Limagrain, offer high nutritional and disease resistant benefits to livestock producers and are on the BSPB Recommended List for England and Wales.

Sinclair McGill’s Colossal Silage and Pasture Renovation mixtures will include new variety Udine. This tetraploid Italian ryegrass has the highest dry matter yield among those on trial in the year of sowing and is 13% higher than the control tetraploid.

“One of Udine’s key benefits is its disease resistance package,” says Limagrain’s grass seed manager Ian Misselbrook. “It scores in the top third among tetraploid Italian ryegrasses for all the main diseases. Which brings added benefits to Colossal Silage and Pasture Renovation – two high yielding short term mixtures predominantly used for cutting.”

Sinclair McGill mixtures Castlehill and Early Start will now include the new grass variety Pensel. This intermediate tetraploid perennial ryegrass is highly nutritious with a good sugar content and it is highly digestible. Conservation yields are especially high in its first year.

“Pensel stays leafy for longer than many other intermediate perennial ryegrasses so it is ideal in a mixture used for summer grazing when other varieties are under-performing,” adds Mr Misselbrook.

“It’s an ideal variety to include in Castlehill, which is a highly successful long term dual purpose ley mixture, and in Early Start that is designed for early spring production of quality grass.

“And very importantly, Pensel adds disease resistance benefits to these mixtures with the highest scores for Crown Rust resistance among intermediate tetraploids and excellent scores for Drechslera and mildew resistance.”

Castlehill mixture will also benefit from the addition of a second new grass variety, Timing. This diploid late perennial ryegrass is a high yielding variety for both grazing and conservation.

Timing has a great seasonal distribution of grass so it can be grazed from early summer until late autumn. It has a dense ground cover, making it more resistant to poaching than many other ryegrasses.

“Castlehill is Sinclair McGill’s most popular grass seed mixture and the addition of these two new varieties will add to its rock solid performances in yield, nutritional qualities, flexibility and longevity.

“The focus is firmly on improving livestock production from grass cost-effectively so it is important that we incorporate these latest advances in varieties into our high-performing mixtures.”

The Sinclair McGill Grass and Forage Crops Handbook 2015/16 is now published with comprehensive details on mixture selection, pest, disease and weed control and the latest developments in the nutritional benefits of selected grass seed mixtures.

Hard copies are available from Emily Short, Limagrain on 01472 370117 or Emily.short@limagrain.co.uk or by downloading an electronic copy from the link below.

A group of 80 lambs for finishing, of mixed breeds and all from the college flock, were grazed on a field with popular varieties of stubble turnips typically used as a fodder crop for grazing sheep and cattle.

“We compared three commercially available stubble turnips; Samson, Hector and Vollenda,” says Robert David, forage crops technician at Limagrain, who ran the trial at Bishop Burton College in East Yorkshire.

A 1.33ha field was drilled with the stubble turnips in mid-August 2015. The sheep moved from grass leys on to the field at the end of November.

“We started them on an area with a mix of the varieties to get them used to the stubble turnips, and after a week we moved the fence and let them on to a section of the fresh crop where each variety was in a defined strip. We put in a back fence to keep the lambs on the trial plots. Two replicates of each variety were included on the trial site.”

Monitoring was in three parts. In mid-November a yield assessment was made of each variety. Then, once grazing started, the number of lambs feeding from each strip was monitored four times an hour during the day, at intervals through the day and for a three week period.

As the back fence was moved down the field exposing a fresh crop each week, a measure of the residual yield was made on the grazed crop to compare the amount of each variety that that lambs had eaten and how much was left.

Although further analysis is still to be published, the initial results indicated a grazing preference for the new variety Hector, followed by the market leading variety Samson.

“Hector is a new variety bred for sheep production and expected to be commercially available in 2017. It is a tetraploid variety with a higher proportion of the root growing above the ground, making it easier for the lambs to access, which may contribute to its grazing preference in this trial,” adds Mr David.

Samson is also a tetraploid variety that produces big tankard shaped purple bulbs. “This variety is already known to be very palatable to sheep, and Limagrain’s recently published trial data for 2016 shows that it produces a root dry matter yield 22% higher than the control variety. We anticipate that Hector will be a fantastic addition to our variety portfolio and the results so far at Bishop Burton College would support this.

Stubble turnips are a fast growing crop which are best sown in July to early August. “They can produce dry matter yields of 4- 5 tonnes/ha in 12 weeks,” adds Mr David. In the trial work at Bishop Burton College, we are demonstrating the benefits of getting the most from this valuable crop by selecting varieties that are grazed in preference to others. This can result in higher intakes and improved live weight gains.”

Third year Agriculture and Resource Management student Ben Hutchinson was involved in monitoring the crop and recording the grazing preferences of the sheep as part of his dissertation project.

“It was interesting to see that certain varieties of stubble turnip were definitely favoured,” he says. “I noticed that by Thursdays and Fridays, the lambs had finished the most popular varieties and had moved on to their less favoured options. This occurred consistently across the three weeks.”

Ben Hutchinson is now analysing yield data of the crop pre and post grazing “I anticipate that this data will support our visual observations and confirm that selecting more palatable varieties will help to improve animal performance.”

With shredlage production the crop is harvested earlier and the process involves a combination of a longer chop length, rolling of the grain to crush the kernel and lengthwise shredding of the stalk.  Typical chop length will be 26-30mm compared to 20-25mm without shredding using a traditional forager.  It is claimed this intensive processing bring a range of benefits.

It reportedly improves the physical effectiveness of maize in the rumen by improving fibre digestibility and encouraging rumination.  Trials at the University of Wisconsin showed increased milk yields with typical US diets.

One of the reasons for the yield response is the greater chop length and physical processing of the chopped material.  With typical US diets comprising up to 70% maize silage in the forage portion of the diet, the chop length of maize will have a marked effect on overall rumen health.

Under UK conditions, diets usually contain a lower proportion of maize, commonly 30% maize: 70% grass.  As grass silage will already have a longer chop length than maize, the impact on rumen health and yield of increasing maize chop length may be less significant.

However, it is likely the approach will be on interest to UK producers, particularly those feeding a higher proportion of maize in the diet.

Although shredlage involves a different processing stage at harvest and may have implications for harvesting dates, Tim Richmond, Maize Manager with Limagrain UK does not believe it fundamentally changes the principles of variety selection, saying that the decision to take a crop for shredlage is more about harvesting stage and management than variety.

“While shredlage processing will have an impact on digestibility of fibre, don’t be tempted to chase higher yields by growing a lower quality variety,” he comments.  “Any improvement will be incremental from the quality of the original plant and the aim should be to grow the best quality crop possible, particularly where it is not certain whether the crop will be taken as shredlage or traditionally harvested.”

He says the first priority should still be to select a variety from the BSPB/NIAB Descriptive List which is agronomically suited to the farm.  “First and foremost varieties grown must be suited to the site class to increase the prospects of a high yielding quality crop.

“Once a short list of varieties has been produced, then select the ones which will produced the highest yield of quality forage, irrespective of how it is harvested.  This will mean focusing on dry matter yield, starch content and cell wall digestibility (CWD).

“As half the total energy is in the leaf and stover, it is the combination of starch content and CWD that drives total ME.  So farmers should look at both starch content and cell wall digestibility (CWD) when selecting the varieties to grow if they want to maximise effective energy yields and production from forage.”

He suggests the processing in shredlage production can be seen as a mechanical way to improve fibre digestibility, but argues that selecting a variety with good CWD is the best starting point as the benefits will be seen in traditional silage as well as shredlage.

To help growers through the decision making process Limagrain introduced the Limagrain Animal Nutrition (LGAN) Accreditation scheme, the first scheme which identifies varieties with the combination of attributes that will deliver superior milk production.

“LGAN accreditation is a farmer’s assurance that the variety selected will deliver higher yields of digestible energy from both starch and the cell wall, leading to increased feed intakes and better production.  To achieve LGAN status the variety’s performance must be outstanding compared with average varieties that have been on the NIAB list at least four years. 

“Don’t assume that mechanical processing will improve quality to the extent that a poorer variety is bought up to the level of a high performing one.  If you grow a poorer variety and then don’t take it as shredlage you will be left with a lower quality feed.  Selecting a better quality cultivar will mean you have a higher quality feed, however it is eventually harvested.”

Mr Richmond says that in the US shredlage will typically be taken earlier than a normal silage crop, being harvested at the half milk line stage, when half the kernel is milky white.  He comments that normally maize will be harvested in the UK when more mature, with less than 25% of the kernel still white.

“This ability to harvest sooner may provide more flexibility and widen the harvest window.  A proportion of the crop could be taken sooner to allow a successor crop to be established earlier.  Cutting sooner could also allow maize to be introduced into the diet more quickly.

“However, harvesting early can have a significant impact on feed quality.  Starch deposition occurs in the last few weeks before harvest, typically between September and mid-October, alongside increases in dry matter content.  Harvesting too early could reduce starch content by over 5%. Therefore it will be important to select early maturing varieties that can achieve a minimum 28% starch by the earlier desired harvest date.

“It is likely that shredlage will offer some advantages to some herds but is unlikely to be a widespread approach, at least initially.  Farmers tempted to try the system should establish the foundations by selecting varieties that will deliver high quality forage, irrespective of how it is harvested and so keep their options open this season,” Mr Richmond advises.