Multi-species grassland mixtures

John Finn and Guylain Grange, Teagasc, Johnstown Castle Environment Research Centre, Co Wexford.

Multi-species mixtures – variety is the spice of life!

Multi-species grassland mixtures are being talked about a lot. Visiting groups to Teagasc Johnstown Castle in 2019 all insisted on a visit to our mixture experiments. Mixtures are expected to benefit grassland production because of the yield advantage from nitrogen fixed by clover, the variety of rooting structures allows them to access a wider range of soil water and nutrients, and their canopy structure that allows them to intercept more sunlight. In addition, they are associated with lower parasite loads in livestock, reduced greenhouse emissions, and increased carbon sequestration. Here, we give a brief overview of some of our current research on mixtures.

How many species?

The question we are most often asked is how many species should be in a multi-species grassland mixture? The answer to this depends on what you want from the grassland, and the growing conditions. We have largely focused on forage yield and quality, but are also interested in gaseous emissions intensity, carbon sequestration potential and weed suppression. In general, a modest number of about 3 to 6 species seems to be optimal in intensively managed grasslands. Any fewer and you may not maximise the benefits; any more, and it becomes difficult for some of the species to persist, especially in regularly grazed or harvested swards. What is probably most important is the type of species, and the inclusion of legumes is fundamental for the incorporation of symbiotically fixed nitrogen.

Yield benefits from mixtures: more from less

Multi-species mixtures offer an opportunity to reduce the use of inorganic fertiliser, without compromising forage yield. With the emphasis on reductions in greenhouse gas emissions for grassland systems, there is a clear focus on reduced use of inorganic nitrogen fertiliser, and its embedded emissions. In a common experiment across 31 international sites (from Canada, to Italy and Iceland), the total annual yield of four-species mixtures (two grasses and two legumes) consistently yielded better than the average of the four monocultures, and even yielded more than the best-performing monoculture in a majority of cases. Multiple plot experiments at Teagasc Johnstown Castle have shown the same: multi-species mixtures consistently out yield monocultures (including perennial ryegrass) when fertiliser application is about 150 kg/ha/year of inorganic nitrogen. Current research by Guylain Grange (a Teagasc Walsh Scholar) shows that combining two grasses, two clovers and two herbs with 150 kg/ha/year of nitrogen out-yielded a perennial ryegrass monoculture with 300 kg/ha/year of nitrogen (Fig. 1, averaged across 2018 and 2019). Under these conditions, we achieved higher yields from less inputs. Similar positive effects of mixtures arose from the SmartGrass experiment.

Environmental benefits

As indicated above, the inclusion of clover in swards can displace the use of mineral nitrogen fertiliser. In addition to saving costs and labour, legume-based mixtures can reduce potential greenhouse gas emissions. In swards which contain chicory or plantain, it will also help lowering greenhouse gas emissions and nitrate leaching. Preliminary results from Saoirse Cummins (a Teagasc Walsh Scholar) showed that the annual greenhouse gas emissions from multi-species mixture were lower than in high input perennial ryegrass, even though the mixture yield was higher (Fig. 1).

Mixture experiments under grazing

Most mixtures experiments have been conducted under cutting conditions (simulated grazing), and there is a need to investigate and demonstrate mixtures under grazed conditions in Ireland. At Teagasc Johnstown Castle, we are sowing and comparing lower-nitrogen (100 kg/ha/year) multi-species mixtures and higher-nitrogen (200 kg/ha/year) ryegrass-clover swards. These are currently being implemented in our dairy and beef farm at Johnstown (and at Curtin’s, at Moorepark). To date, the dairy herd at Johnstown is grazing happily on the mixtures, and 2020 will be the first year that we can compare milk quantity and quality. In the meantime, we are keen to learn how best to manage these swards.

There is no reason to believe that mixtures cannot be beneficial under grazing. In a two-year grazing experiment (with 75 kg/ha/year of nitrogen fertiliser) in France, an increase of mixture diversity from one to five species (two grasses, two clovers and chicory) resulted in positive effects on animal performance. Compared to ryegrass-clover swards, multi-species swards improved pasture intake (+ 1.5 kg DM/day), production of milk (+0.8 kg/day) and milk solids (+0.04 kg/day).

Research by Thomas Moloney (at Teagasc, Grange, as part of the SmartGrass project) showed that under favourable ensiling conditions, two-species and multi-species mixtures preserved comparably to perennial ryegrass. Under more challenging conditions, they had a greater requirement for rapid wilting and/or adequate effective additive.

Mixtures can help mitigate effects of drought

Climate models indicate that summer droughts will become more frequent and more severe. In Europe, this means that grasslands will be increasingly subjected to intense winter rain precipitation and summer droughts. In a two-year experiment in and another in 2018, we have found a positive relationship between plant diversity and yield stability in intensely managed grassland, even under experimental drought conditions. The benefits of multispecies mixtures were so strong that yields from a mixture of species under drought conditions matched or exceeded yields for monocultures under normal rainfall conditions (Fig. 1).

Persistence of species over time

In general, multi-species mixtures are excellent at suppressing weeds. This is important because a post-emergent spray is not possible. Over time, clover content will reduce if large quantities of mineral nitrogen are spread. However, lowering fertiliser quantities in summer will favour clover growth. Ensuring clover (and herb) persistence over time (more than 4 years) is likely to be the biggest issue. This is possible with appropriate management. However, this topic requires more research on optimal management of mixtures under grazing and soil types, improved breeding for persistence in mixtures, and mitigation actions such as oversowing of seed.

Multi-species mixtures can be an effective, farm-scale practical action to maintain or increase forage from less inputs. They can also mitigate the effects of severe weather events such as drought. Combined with their other benefits, mixtures offer a strong potential to improve the sustainability of livestock production.

Championship is won on the pitch - walk your farm

John Douglas Teagasc, Animal & Grassland Research and Innovation Centre, Grange, Dunsany, Co Meath

Fergus Bogue Teagasc, Animal & Grassland Research and Innovation Centre, Moorepark, Fermoy, Co Cork

Just as a football player can win or lose a match on the pitch, the place to manage grass is out on the field too. According to PastureBase Ireland, the average grass growth is 60kg DM/ha and is operating at an average of 750kg DM/ha (186kg DM/cow).

Figure 1 shows the projected grass growth for this week for 55 farms across the country using the Teagasc Moorepark Grass Growth Model. There is large variation in the predicted grass growth rates being largely influenced by soil type and whether a farm got rain or not in the last three weeks. The rage in predicted growth rates are from 35 to 119kd DM/ha per day. Farms in the eastern part of the country are most affected by the below normal rainfall. However, some have satisfactory growth rates depending on location and soils type. Growth rates in the south and south west will be above normal this week.

Figure 1: Grass growth prediction from the 18th to the 24th of May 2020 for 55 farms throughout Ireland

The main message from Grass10 is to walk your farm, estimate your grass cover and growth rate and take action early. There are two scenarios currently on PastureBase farms:

Farms where growth is high, particularly heavy soils & areas that have got rain

Areas that have received rain and farms on heavy soils; particularly in the south and west of Ireland, are experiencing high growth rates (70kg DM/ha to 80kg DM/ha) and managing grass quality is the challenge on these farms. Surplus bales are being cut to keep pre-grazing yields at 1,400kg DM/ha.

Figure 2: Sean Kelly, dairy farmer, Nenagh, walks the farm twice weekly to make decisions and maintain grass quality.

By keeping quality grass in front of livestock, animal performance (milk solids/liveweight gain) is higher, graze-outs are tighter (4cm) and regrowths are quicker (Figure 2). Grazing “strong, stemmy” grass will compromise performance and result in poor graze outs plus reduce recoveries (poorer quality grass for the next rotation).

If there is adequate grass supply on the farm:

  • 1 Keep pre-grazing covers at 1,400kg DM/ha (9-10cm).
  • 2 Graze down to 4cm to ensure high-quality grass for the next rotation.
  • 3 Minimise the supplement being fed to livestock to capitalise on this grass, eg on a dairy farm, cut back meal feeding to <2 kg/cow (make sure magnesium is covered).
  • 4 On heavy soils or areas that have received rain (where growth is 70kg DM/ha +), surplus bales should be cut to keep average grass cover/cow at 160kg DM/LU to 180kg DM/LU or 10 to 12 days ahead for drystock farms. This will keep pre-grazing covers at 1,400kg DM/ha.
  • Figure 2: Sean Kelly, dairy farmer, Nenagh, walks the farm twice weekly to make decisions and maintain grass quality.

  • 5 Where growth rates are good, be ambitious when taking out surplus paddocks. It is often the case that one paddock too few is taken out, leaving the issue of heavy grass on the farm not fully corrected. Consult a Teagasc adviser if in doubt.
  • 6 Match growth and demand on the farm, eg if growth is 65kg DM/ha, demand should be 65kg DM/ha (4 LU X 16kg DM grass = Demand 64kg DM/ha).
  • 7 Maintain a rotation length of approximately 20 days; this means that you should be grazing 5% of the farm on a daily basis.
  • 8 Take the opportunity presented by good conditions to harvest main crop first cut silage in May. This will put quality in the pit and allow for a good yield of second cut.
  • Farms where growth has been reduced due to a soil moisture deficit

    The second scenario on farms is where grass growth rates have reduced due to below-normal rainfall over the last three weeks. Many farms in the eastern part of the country have received little or no rain since 1 May. These areas are experiencing high soil moisture deficits (30mm to 60mm; Figure 3), which has curtailed growth to less than 40kg DM/day in some cases.

    Figure 3: Picture: Soil Moisture Map (Met Eireann)Farmers experiencing low growth rates should act early. Avoid cutting surplus bales, bring more area into the rotation and supplement if necessary to hold average farm cover

    If grass growth rates are below normal:

  • 1 Walk your farm to establish you farm grass growth rate and average grass cover. Watch the weather forecast and see if there is rain forecast for your farm. Keep N fertiliser up to date for now and review in June if drought persists.
  • 2 It is better to act sooner rather than delay until the farm is grazed bare. If farm growth has slowed to <40kg DM and the farm is in a “green drought" situation the priority is to maintain average farm cover on the block above 400kg to 500kg DM/ha (130kg DM/cow at 4 cows/ha) for as long as possible. This will aid recovery when rain arrives.
  • 3 If grass is disappearing off the farm, drop daily grass demand to match growth rate immediately. For example, if stocked at 4.0 cows/ha and growth is 40kg DM, the aim should be to feed no more than 10kg grass/cow (4x10 = 40) and supplement the balance of the diet up to 18kg DM with meal and silage.
  • 4 Deficits of up to 5kg DM/cow/day can be met with parlour concentrate. If more than this then silage will need to be fed. If feeding silage to livestock, feed it out daily so it is fresh and will all be used. Round bales cut from outside blocks can fed back to livestock straight directly after harvesting. Allocations should be eaten with 24 hours to avoid spoilage.
  • 5 Once action is taken, it is essential to track changes in farm cover to make sure 1) supplement is having the effect of holding cover and 2) supplement is removed quickly enough when growth recovers Use the predicted Grass Wedge and the Predicted Growth Model in PastureBase to allow you to project next week’s feed budget.
  • 6 Hold grazing rotation at 24 to 25 days.
  • 7 Avoid cutting surplus bales off the grazing platform if growth is below demand. Grass will grow grass in a soil moisture deficit.
  • 8 If there are paddocks that had been closed off for surplus bales, these should be grazed. Clean-outs will not be ideal so strip-graze with a 12-hour wire of covers are 1,600kg DM/ha. Mix and match grazing these heavier covers with lower covers on the grazing platform.
  • 9 If possible reduce stocking rate in the grazing platform; remove non-lactating animals to outside blocks if possible.
  • The Grass10 campaign is kindly sponsored by - Teagasc, The Department of Agriculture, Food and the Marine, Grassland Agro, AIB, FBD and The Irish Farmers Journal.

    Lodging and brackling control in spring barley

    Dr Richie Hackett and Michael Hennessy, Teagasc Oak Park, Carlow

    Spring barley has established very well in many areas and appears quite lush, although in some areas lack of rainfall after sowing has hindered establishment.

    A common question that arises at this time is whether or not a plant growth regulator (PGR) should be applied. There are two reasons why a PGR might be applied to spring barley, to manipulate tillering or prevent lodging. There is relatively little research to support PGR use for either reason for the vast majority of barley crops.

    Research at Oak Park and abroad has looked at the PGR effects on tillering and yield, and while there can be sometimes transient effects on tillering, these effects rarely persist to harvest with the net result that no yield benefit is achieved. At Oak Park this was as true for crops sown at very low seed rates, as for crops sown at normal seed rates.

    Use of PGR for lodging control in spring barley should only be contemplated if there is a very high risk scenario (very fertile soil, high organic or fertiliser N inputs) and then the best approach may be to wait until the crop is at around GS32 and assess the crop at that stage. However, PGR effects on lodging are likely to be less in spring barley than winter barley, reducing fertiliser inputs will have a bigger lodging reduction effect than PGR. Observations from many nitrogen response trials over the years would indicate that lodging normally only occurs where well in excess of the optimum N amount for the crop has been applied.

    In any case, if the current dry conditions persist lodging is unlikely to be an issue as lack of moisture will act as a natural growth regulator (think 2018). It must also be remembered that PGR can be stressful on crops, particularly if used in complicated tank mixes, and as many crops are under stress as a result of moisture deficit adding another stress is not advisable.

    It can often be the case there is some confusion between the terms lodging and brackling. Lodging is where the plant falls over due to roots giving way or where bending/twisting of the lower stem during the mid-late part of the growing season. Both types giving rise to the crop lodging close to the ground.

    Brackling in a crop occurs close to harvest. Brackling (which also includes necking) is where the stem breaks, generally from midway up the plant, with necking associated with breakages closer to the cereal head.

    As mentioned above PGR can have some, but limited effects on lodging but have little or no effect on brackling. Therefore it’s a waste of money including PGR into the tank with the justification that it will help brackling.

    Disease control

    Results have shown the best way to reduce brackling is to get excellent disease control, especially of Ramularia, but other factors such as adequate potassium (K) applied early to the crop will also help. However, these measures will not achieve total elimination of brackling. So for this year it’s too late for many of the solutions outlined above other than achieving good disease control.

    However, planning for next year’s crop can begin immediately to put in place all measures you can which will result is a standing crop at harvest.

    Trends in Irish pig production figures

    Gerard McCutcheon, Teagasc, Oakpark Research Centre, Carlow

    Production and financial records from pig farms using the Teagasc e-Profit Monitor (ePM) system are compiled annually into a national herd performance report. The data includes well over 50% of the pigs farmed in Ireland. There is over twenty years data compiled. A lot has changed in that time and this article examines some of the main differences in key performance figures over the last 20 years.

    Born alive per litter

    One figure that has a huge bearing on the number of pigs produced per sow per year is the number of pigs born alive per litter. In 2003 the born alive per litter increased above eleven to 11.01. It wasn’t until 2010 that the 12.01 born alive was reached. In 2016 the 13 born alive was exceeded and, three years later the 14 born alive per litter was achieved.

    As the born alive increased we also see a steady increase in the number of pigs produced per sow per year (Table 1).

    Growth performance

    Each year the growth rate of pigs has improved. This improvement is quite impressive when viewed over twenty years. The figures cited in Table 2 below are from the time the pig is weaned to the time it is sold.

    The liveweight at sale has increased by over a kilogram (kg) each year over the same period. The number of kg of feed required to achieve one kg of live-weight (feed conversion efficiency) has remained relatively static at 2.44 over the past ten years – even though the sale weight increased by 10.6 kg (Table 2).

    The growth rate (Average Daily Gain or ADG) increased by 139 grams per day over the twenty year period mainly as result of improved genetics, and, the ability to achieve a heavier pig at sale (Table 2).

    Feed required to produce carcase gain

    The total “pig meat per sow per year (kg)” is calculated by multiplying the number of pigs produced per sow per year by the average carcase weight. The second item is the “tonnes of feed /sow /year”. This is calculated by adding the total tonnes of all feed used in the year and dividing it by the average sow herd size. These figures are in Table 3.

    The output of pig meat per sow was 1,471 kg twenty years ago and required 5,385 kg of feed to produce this. This is a requirement of 3.66kg of feed per kg of pig meat produced. The 3.58 figure in 2019 is better and shows a slow improvement on this parameter.

    Conclusion

    Irish pig production is becoming more and more efficient. This is testimony to the hard work and investment of resources at farm level to try to improve competitiveness in the international markets in which we compete.

    Helping farm families is what drive Teagasc advisers

    These highly educated young advisers quickly learn how diverse the job is and how to apply their knowledge to solving real life challenges for farm families.

    Paddy Browne, drystock adviser, Ballybofey, Teagasc Sligo/Leitrim/Donegal Region

    Paddy studied Agric & Environmental Science in UCD before completing an MSc. in Geographic Information Systems (GIS) and Remote Sensing at the University of Ulster.

    It’s always vital to speak to farmers “in their own language” and Paddy, a fluent Irish speaker, does literally that by regularly featuring on Barrscéalta, a Radio Na Gaeltachta programme.

    “The show includes farming topics and the pressures farmers are under, offering advice and guidance. It is a national radio broadcast targeting the Gaeltacht speaking regions that range from Donegal – Kerry,” says Paddy.

    Paddy was previously a Teagasc education officer and mentored many young people when they were completing their Green Cert. “It is important to help these future generation farmers to implement the skills and knowledge that they have learned, to improve their family farm,” says Paddy. “Be it on the radio, at beef or sheep discussion groups, on farm or on the phone, it’s all about helping farmers make progress.”

    Aine O’Riordan, drystock adviser, Macroom, Teagasc Cork west region

    “I started with Teagasc as a Walsh Fellow student in the MAIS programme focusing on how Teagasc can make best use of social media such as Facebook and Twitter, based in Clonakilty Agricultural College. “I took a post teaching in Clonakilty before moving to my current role in 2016. I work with suckler, beef and sheep farmers and really enjoy discussion groups and farm visits. I have a keen interest in rural development and farm diversification as well as technical advice.

    “When I was just starting out as an adviser I convinced a farmer to weigh his weanlings regularly to monitor their performance and daily liveweight gain,” says Aine. “It’s really satisfying when you can encourage someone to make progress in whatever part of their business. As well as improving production I encourage farmers to “think outside the box” in terms of extra farm income. There are so many options such as agri tourism and food if you are willing and open to diversification.” Aine’s hobbies include GAA, cattle breeding and country music.

    Nigel Kennington, dairy adviser, Kilkenny, Teagasc Kilkenny/Waterford region

    After studying animal science in UCD, Kilkenny native Nigel began his career at Teagasc Kildalton teaching students. Subsequently he moved to Clonakilty, west Cork, covering the intensive dairying regions of Bandon/Innishannon.

    “I really enjoy being able to help farmers to make decisions that will benefit them, not only in the short term but also for years to come. For example, working with discussion groups or individual farmers, to pick teams of AI bulls to use on their herds. This is important work as the decisions made should not only help to continue to improve the short-term genetic potential but also contribute to the performance of the herd into the future.”

    Today, Nigel is still working as a dairy adviser but based in Kilkenny covering the Callan/Tullaroan/Kilmanagh area. “Being an adviser is a very varied role and you have to be adaptable, for example in the current situation, changing the methods of delivering four discussion groups from on-farm-based meetings, to delivering to groups through conference calls/online. The main thing is that we are still able to work directly with farmers, and contribute to them making the best decisions for their families and their businesses.”

    Claire Mc Auliffe, dairy adviser, Listowel, Teagasc Kerry/Limerick region

    Claire grew up on a dairy farm in Kiskeam, Co Cork, and completed a degree in animal science in UCD. She then worked with the FRS as a GLAS adviser before returning to education to complete a MAEI masters through the UCD/Teagasc Walsh Scholarship.

    “During the masters I had placements in Navan and Tralee which provided an excellent opportunity to learn from experienced advisers and get practical advisery experience in both drystock and dairying,” says Claire, who completed a thesis on “The role agricultural advisers have in reducing farmer stress.” She is now working as a dairy adviser in Listowel, north Kerry. “Great farmers, sometimes challenging soil,” is her summary.

    “The most enjoyable part of the role is being on farms seeing the outcome of actions you have discussed with farmers months earlier. For the moment that is curtailed by COVID-19 restrictions but we are adapting by facilitating ‘virtual’ discussion groups and phone based advisery service.” As well as her job, Claire enjoys travel, trips to the cinema and following Cork GAA.

    John Conroy, drystock adviser Westport, Teagasc Mayo region

    “The first time I remember thinking that I had really made a difference was when a client asked me what kind of a nut/concentrate he should feed to cattle that he was finishing,” says John. “I advised him to get his silage tested, and then formulated a diet for him based on the results using the Teagasc ration reckoner. It certainly improved his margin and I was delighted to see him benefit.”

    A native of Eyrecourt in east Galway, John graduated from Waterford Institute of Technology in 2017 with a degree in Agricultural Science. He joined the Teagasc/UCD Walsh scholarship masters program. “I got the opportunity to spend a year in Teagasc Dungarvan in Co Waterford, and Teagasc Mohill in Co Leitrim, where I worked alongside with, and learned a great deal from, experienced dairy and drystock advisers.

    “After completing my masters I took up a position as a drystock adviser in Teagasc Westport, where I get great satisfaction from assisting farmer clients and helping them to develop and make improvements. We have maintained strong contact with farmers over the last two months but I am looking forward to getting back out to start visiting my clients once again.”

    Rachel Taylor, drystock adviser, Naas, Teagasc Laois/Kildare/Meath/Louth/Dublin region

    Rachel Taylor is from Straffan, Co Kildare, studied animal science in UCD and then went on to complete a PhD in the Teagasc Beef Research Centre in Grange, Dunsany, Co Meath. Her research focused on factors influencing technical and financial efficiency of suckler calf-to-beef farms.

    On completion Rachel moved to Naas as a drystock adviser with 230 clients whose farming systems range between beef, sheep, tillage and mixed farms. “Every time the phone rings you are faced with a different challenge,” says Rachel. “Be it advice on animal performance, nutrient and feed management, financial planning or scheme work, we have a unique role in helping farmers.

    “Whether they are new entrants; families planning for farm succession or, in some cases, the relatives of those dealing with the estate of a client who has passed away, we aim to assist them all with advice for their unique circumstances. Given the number of challenges the drystock sector has been confronted with over the past decade, and coming from a beef background, I find it very satisfying to assist farmers meet these challenges.”

    Rachel is a member of Kilcarrick Riding Club and competes regularly in dressage and showjumping competitions.