Maize breeder optimistic of a reprieve for seed treatments
Limagrain UK is optimistic that treated maize seed will still be available for the upcoming season as hope grows that the impending ban on seed treatments will be delayed following a successful lobbying campaign.

The future viability of maize being grown in the UK – either for use as livestock forage or as a feed source for AD (anaerobic digestion) plants – has been in question due to an impending ban on all seed treatments including Korit (ziram) bird deterrent, Redigo M (prothioconazole + metalaxyl) fungicide and Force 20 CS (tefluthrin) insecticide.

As it currently stands, from  31st December 2023 it would be illegal to import, sell or sow any seed which has been treated with any of these products, leaving crops at significant risk of failure.

Without a suitable bird repellent, insecticide and fungicide, there’s a substantial risk that newly drilled crops could be completely wiped out by corvid grazing, or seriously hindered by insect damage and soil-borne pathogens,” explains Tim Richmond, Maize Manager for Limagrain Field Seeds in the UK and Ireland.

“Corvids are highly intelligent birds, and quickly understand seed drilling patterns, with any attempt to drill seed deeper to prevent bird damage likely to exacerbate the risk of seedling blight, making the application of a fungicide seed treatment such as Redigo M even more critical.”

To counter the ban, which has threatened the industry as a result of the UK’s departure from the EU, an industry working group – spearheaded by Limagrain UK – has been set up to lobby the Government into taking action.

Limagrain has taken a leading role in this sector-wide campaign which has also included the MGA, AIC and NFU,” Mr Richmond continues. “A number of emergency authorisation (EA) applications have been made to the regulators for the continued use of these treatments for sowing in spring 2024, with a decision on whether the ban will be withdrawn or delayed due imminently.”

The Expert Committee on Pesticides is scheduled to meet in September, with a final announcement are expected to be made before the end of the month.

“As things currently stand, we’re confident that our ongoing discussions with the Farming Minister, the Rt. Hon. Mark Spencer MP, will have a favourable outcome and that all three seed treatments will still be available for use in 2024 – either as a result of the Emergency Authorisations being granted, or because of a change in the law to delay the withdrawal date.”

Despite the imminent announcement there remains significant uncertainty amongst UK maize growers, with some already suggesting they are preparing to sow an alternative crop such as wholecrop winter wheat.

“We appreciate that the clock is ticking and that for some growers any announcement might come too late,” Mr Richmond adds. “But until a concrete decision has been made, we’d urge growers not to rush into making any changes to next year’s rotation.

“We will know more in a relatively short timeframe and will announce the Committee’s decision as soon as it has been made known to us. In the meantime, we are continuing to lobby for the new generation of maize seed treatments to be registered with the CRD as quickly as possible to ensure maize remains a viable crop in the UK in the long-term.”

Limagrain UK will be exhibiting at the UK Dairy Day in Telford on Wednesday 13th September. Please feel free to visit stand H120 to discuss the latest situation with a member of the LG team.
Korit® Pro Safety Information

Essential safety information for Korit® PRO seed treatment

Download the safety information for Korit® PRO, which contains details of active ingredients and safety warnings, as well as the safety equipment required for using, handling, storing and transporting seed treated with this chemical.

The safety card also contains information regarding good practices for using the product.

Download the full Korit® PRO Safety Card here



For each step, use the safety equipment required!

Transport and Storage

Check that all the bags are intact

During transport, users and seeds bags must be physically separated (ex: in a trailer)

Transport bags in the original packaging

Store in locked up and well-ventilated place. Keep container tightly closed

Dispose of contents/container in accordance with local regulations

Collect spillage


Before Sowing (when opening the seed bags and filling the seed drill hoppers)
Avoid exposure to dust

Avoid the transfer of dust from the seed bag into the seed drill hoppers.

Do not reprocess treated seed with additional products


During Sowing
When using a pneumatic vacuum seed drill, the dust from the treated seeds must be directed towards the ground surface by using deflectors.

To protect birds and mammals, treated seeds must be well covered with soil, including at the end of the furrow.


After Sowing
Do not leave empty bags or treated seeds unusable in the environment. Eliminate them in accordance with current legislation.

Return all unused treated seeds to their original bags and do not reuse empty bags for other uses.

Do not use treated seeds for human or animal consumption or to produce derived products.

Wash your hand and all exposed parts of your body before eating and after work


H330 | Fatal if inhaled
H410-H400- H411 | Toxic or very toxic to aquatic life
H317 | May cause an allergic skin reaction
H335 | May cause respiratory irritation
H373 | May cause damage to organs through prolonged or repeated
In case of a medical emergency following exposure to a chemical, call:
NHS Direct in England or Wales 0845 46 47 or NHS 24 in Scotland 08454 24 24 24 (UK only)
Could increased maize acreage help drive forage productivity?

Milk from forage continues to be a high priority on dairy farms, fuelled by increasing purchased feed prices and the impact of the reduction in Single Farm Payments. 

“We are seeing higher prices for all feed commodities,” comments Tim Richmond, Limagrain Field Seeds Maize Manager UK & Ireland. “This is putting pressure on margins, especially as the difficult silaging season in 2021 means many grass silages are lower than average quality and will require higher levels of supplementation.

“At the same time, dairy farmers are having to plan for life with reduced Single Farm Payments. The average dairy farm will see a reduction of 25-35% in 2022, rising to 40-50% in 2023, which will see farm income reduced by around 1ppl.

“So the challenge will be producing more, better quality forage to help reduce the impact of these economic factors. I would advise starting forage planning now, and in particular to consider opportunities for increasing maize acreage. As a starch-based forage it can complement high quality grass silages extremely well and this year is helping cows make the most of this year’s grass silage which is higher in fibre, and slightly less digestible than normal.”

He says even in a difficult maize season like 2021, crops generally performed well. The wet cold weather in April delayed harvest, but later sown crops did not suffer.

“Early sown crops drilled into cold soils struggled to get away, with the seed sitting and sulking. Where drilling was delayed until soil conditions were optimum, crops got away very quickly and were ready to harvest at the same time as earlier sown crops – provided care had been taken with variety choice.

“While most of our trial sites around the country were drilled in mid to late April and harvested in early October, the site at Bangor-on-Dee was not sown until late May.

However, the plots were all mature and ready to harvest in mid-October, making up over two weeks of the lost time. All yielded well and even the later maturing varieties came off at over 30% dry matter.

“New earlier-maturing varieties with strong early vigour mean you can manage by the conditions rather than the calendar and still get crops harvested in good time and in good conditions.”

Mr Richmond believes if dairy farmers want to increase forage productivity for next season, then maize is a serious contender and says it is worth asking the question about whether more maize could be grown (see flowchart).

“The first point to stress is that if your farm isn’t suitable for maize, then don’t try and grow it. Similarly, if some land is suitable but some is not, don’t try and push acreage. But if you have suitable fields, then it is certainly worth taking a close look at. By selecting an earlier variety it might be possible to grow a crop successfully on more marginal land.”

He says they are many varieties that are now available which will mature at least a week sooner than others, requiring fewer Ontario Heat Units to reach full maturity. Earliness is defined by the FAO for the variety; the earlier the variety the lower the FAO. If you have a shorter growing season or a marginal site, selecting an earlier variety will reduce the risk of variable weather delaying harvest and will increase the chance of the successor crop being established.

Use the Maturity Manager tool to see how many OHUs are available in your postcode

To simplify variety choice, the LG Maize Manager App which is available on the Apple or Google Play stores, or at  Here, growers can find the Maturity Manager tool. Developed with the Met Office, it shows the average heat units for your post code and recommends suitable varieties.

“Having identified varieties suitable for your area, the Feed Manager tool allows you to compare varieties on their expected output and milk production potential.  Selecting a variety like Prospect or Resolute, for example, will ensure a higher quality feed and the potential to increase milk from forage significantly.

Mr Richmond comments that where maize is currently grown, it may be worth considering following it with a crop like Westerwolds/Italian Ryegrass, to ensure a successor crop is established and contribute additional forage for the spring. “Sowing Westerwolds, Italian Ryegrass or Humbolt forage rye will prevent soil run off and improve retention of nutrients in the soil while building soil organic matter.  Westerwolds and Italians are suitable for grazing or cutting while Humbolt forage rye can be grazed, zero-grazed or baled. All offer flexibility and will increase total forage output per hectare.”

If there is not scope to grow more maize on the existing acreage, Mr Richmond points out that having maize grown under contract could be a realistic option for dairy farmers in most parts of the country. He says there is increased interest among arable and dairy farmers alike, as it is an arrangement that can bring big benefits to both parties.

He emphasises that it is important to acknowledge that the objectives of the two parties will often be different. The livestock farmer will be interested in the yield of quality forage to maximise the benefit to his business and his return on investment when buying the crop, focussing on characteristics like dry matter yield, starch content and cell wall digestibility.

The grower will be more concerned with how the variety will suit the rotation that it will mature quickly enough and be harvested in time to allow the autumn sown successor crop to be established.

“But both parties can benefit. The dairy farmer can increase the proportion of maize available without compromising the system at the home farm.  They also have no responsibility for the growing of the crop and can benefit from the arable farmer’s expertise.  They can budget the tonnage they should receive and will be involved in key decision making such as harvesting date.

“The grower has an additional cash crop and can use maize to improve the overall rotation. Agronomically, maize can prove particularly effective on farms wanting to control problematic weeds like blackgrass.”

Mr Richmond explains that under a typical arrangement, a farmer contracts to grow a set acreage of maize. The grower covers the growing costs, while the buyer pays the costs of harvesting and pays a set price per tonne grown. The buyer will arrange the harvesting with the contractor in consultation with the grower. In some cases, the buyer may supply slurry to the grower and this will be reflected in the price.

“Structured in this way, both parties can benefit, but it is vital for each to understand each other’s objectives. The grower will want a crop that fits in with the system and this will usually mean an early maturing crop, allowing a successor crop to be established. As payment is often on a per tonne freshweight basis, physical yield will be important.

“For the purchasing dairy farmer on the other hand, the objective of ensuring sufficient yield will be a priority, but quality will be increasingly important.  Quality forage will be required to increase energy intakes, to boost overall dry matter intakes and maximise the return on investment.

“Variety choice is the basis of any agreement and ensuring the objectives of both parties are met.”

Mr Richmond says both parties should be involved in the discussion on variety choice.  He says that it is possible to select a variety with early maturity and good yields to meet the grower’s objectives, at the same time having exceptional feed value to deliver the quality the dairy farmer needs.

“For arrangements requiring a very early variety, then Gema and Dignity would be an excellent choice as they both produce high quality, energy-dense forage, but are suited to a short growing season, allowing a successor crop of winter wheat to be established.

“For farmers looking to optimise forage milk production potential without risking a delayed harvest, then Prospect, Saxon and Resolute are outstanding candidates.

“In parts of the country where more heat units are available and conditions and site class mean higher yielding and later FAO varieties are a practical option, then Mantilla and LG31.207 would be good choices, producing plentiful yields of high energy feed.”

“With the pressure on margins, increasing milk from forage remains a priority. In many parts of the country, maize can offer a flexible way to increase total forage production and take control of your feed costs.

“And with fertiliser prices rising quickly, it has the attraction of being a lesser user of nitrogen.  In addition as the biggest demand for nitrogen is at stem extension, one option would be to apply less in the seedbed and apply foliar nitrogen later – by which time we might see a weakening in fertiliser prices,” Mr Richmond concludes.  

Variety choice for maize break crops

Maize is increasingly seen as an alternative break crop on arable units, and by selecting the right variety you can ensure a good crop and the timely establishment of a successor crop.

Maize was often seen as a challenging crop to grow due to the late harvest. However, new earlier maturing varieties mean the crop can fit very well into rotations, allowing successor crops to be drilled in good conditions and in good time. While not a full alternative to oilseed rape, which will usually provide a better return on investment in most years, maize can be incorporated into rotations as a way to increase the break crop area and leave a good margin. Agronomically, maize can prove particularly effective on farms wanting to control problematic weeds like blackgrass. The crucial thing to look for is early maturing varieties that will suit your site’s conditions, as you need a variety which will mature at the right rate for your farm to ensure a timely harvest and successful establishment of a successor crop.

Try our OHU Calculator to find the right variety for your location

Maize maturity is all about heat, which is expressed as Ontario Heat Units (OHU). Maize needs to accumulate a minimum of 2500 OHU, before being fit to harvest. The fewer OHU required, the earlier a crop will be ready to harvest. Earliness is defined by the FAO for the variety; earlier varieties have a lower FAO. They can be ready to harvest as much as two weeks earlier than later maturing ones, which can make a big difference to crop success. If you have a shorter growing season, selecting an earlier variety will reduce the risk of variable weather delaying harvest and will increase the chance of the successor crop being established. Look for varieties with an FAO of 140-220, to ensure you get a variety that will mature in good time. Varieties like Resolute, Saxon and Mantilla, all combine early maturity with excellent yields, while Gema with an FAO of 150, is very early maturing. To simplify variety choice for your site, download our unique Maize Manager App, available free on the Apple or Google Play stores! The Maturity Manager section was developed with data from the Met Office. It shows the average heat units for your postcode and then lists varieties which are suited to your farm, and will mature within the average accumulated OHU. The Maturity Manager will allow you to make an informed choice and select the optimum variety – reducing risk, ensuring an effective break crop and the establishment of the successor crop.

Crimped maize can increase feeding options

Richard Camplin, Technical Manager

Faced with escalating fertiliser costs and the prospect of tight feed ingredient markets next winter, the importance of maximising feed output from your own resources will remain a priority for dairy farmers.

According to Richard Camplin, LG Seeds Technical Manager, farmers who are able to grow maize, or who can work in partnership with an arable neighbour who is happy to grow the crop could benefit from increasing the acreage grown this year. “There is still time to get maize in the ground and it could be used to increase forage output with reduced reliance on fertiliser. Maize requires less fertiliser per tonne of dry matter than grass and a large proportion on maize requirements can be met from slurry. “Alternatively, it could be used to produce crimped maize to help trim the requirement for purchased starch sources. Careful variety selection can allow a degree of flexibility to be retained about how crops are utilised as the season unfolds.” He says advances in plant breeding mean there have been massive improvements in the standing ability and disease resistance. New hybrids such as Prospect, Pinnacle and Resolute now have the combination of improved agronomy plus the advantages of superior digestibility and high starch yield, making them ideal for quality forage and also for crimping.” If 2022 is a better than average grass growing season so grass silage yields are higher and if maize crops grow well, Mr Camplin the situation might develop where a proportion of the maize could be crimped to help reduce the requirement for purchased starch sources for the TMR. Crimped maize is typically a 65-75% dry matter feed with 14.0-14.5MJME/kgDM and 60-70% starch making it a valuable ingredient in diets. Having been processed prior to clamping, it is a rumen-friendly feed with a higher proportion of bypass starch.  It can be clamped or stored in AgBags.

LG Grain Trial, Leicestershire

LG has been running UK trials looking at crimping potential and Mr Camplin advises that variety choice allows flexibility of use to be a real option. “We ran trials on three locations with an average 27.5% moisture at harvest with the wettest crops being 33%. As the crops are harvested around six weeks after silage would have been taken, it is vital to be growing early maturing varieties and to allow the maximum growing season. So I would recommend not making crimp from later drilled crops. “Early maturing varieties that performed best in the trials are LG30179, Prospect, Resolute and Pinnacle, so growing these varieties would give the option for quality forage or a crimped crop (see table).” He stresses the importance of selecting a variety suited to the farm and to look for varieties with low levels of disease and high standing ability and lodging resistance. As crops are harvested later it is essential they stand well.  Bad infections of fusarium, for example, can lead to fusarium stalk rot which can weaken the stem and increase the lodging risk. If a crop is being planted specifically for crimped maize, he advises it is usual to reduce the seed rate to 85,000 seeds/ha. This is primarily to help bring maturity forward but this is less of a concern if an early variety has been chosen as they tend to have good cob maturity. However, having more space and light will help improve cob size and starch content. “If a grower is interested in growing a crop guaranteed to produce high quality forage but which could be switched successfully into crimping to maximise the contribution from maize the key will be choosing an early maturing variety with good feed quality and the best agronomics. “In this way, maize can provide a flexible way to meet the challenges of feeding cows this winter,” Mr Camplin concludes.   Crimp grain yields from early maturing varieties 2021.

  Fresh Grain Yield Grain Dry Matter
Variety t/ha @ harvest @ harvest
Pinnacle 10.7 72.1
Resolute 10.5 70.7
LG30179 9.8 74.9
Prospect 9.6 74.7