With maize drilling likely to start in less than 10 weeks, now is the time to finalise the details of managing the crop.
Maize seed may already be in the shed, but the decision on a suitable inoculant or strategies for protecting against bird damage need to be considered.
This is according to Roy Eastlake, LAN UK technical support manager, who says holding a meeting between the farmer, the nutritionist, agronomist and contractors to discuss managing maize from field to clamp is time well spent.
He says: “Bringing the key members of the team together as soon as possible to discuss this year’s maize crop will allow targets to be set relating to quality and quantity.
“A step-by-step plan should be agreed for crop establishment, management in the field, preparation and harvesting, clamp management and feeding out.
“Reflecting on previous years’ crops and what went well or perhaps did not work so well will help the team identify how to do better this year.
“For example, agree who will carry out regular crop walking to assess the rates of maturity and dry matter [DM] development and help estimate target cutting dates more accurately.
“Then make sure the contractors are bought into the timetable.
“Discuss which stages of the process could be improved to deliver more consistent quality, whether it is consolidation in the clamp or avoiding problems such as aerobic stability.
Involving all members of the team at the earliest opportunity will ensure everyone understands their key tasks and responsibilities.
“It may be worth considering a different payment arrangement if you use contract growers.
Some growers are now offering an incentive-based payment based on starch and DM levels so it is in everyone’s interest to cut at the right time and take care with each stage of the process.” While the quality of the silage made will be influenced by the variety chosen, time of harvest and clamp management, Mr Eastlake says using a suitable inoculant can help promote the desired fermentation process, thus improving quality and aerobic stability.
He says: “It is the yeasts and moulds on maize silage which cause aerobic spoilage because they break down lactic acid causing the pH of the silage to increase and, in the process, use up energy and create heat.
“This allows less desirable bacteria, such as clostridia and entero-bacteria, to multiply, producing butyric acid, which reduces silage palatability and increases levels of waste.
“An inoculant such as Magniva Platinum Maize contains heterofermentative bacteria, which produce compounds to kill off yeasts and moulds.
So when the clamp is opened and air enters, these organisms are not present to multiply, thus limiting spoilage and waste.” Magniva Platinum Maize also contains enzymes which aid fibre digestibility and this will improve intakes of maize, according to Mr Eastlake.
He says: “At least half of the energy in a maize plant is in the stem and leaves, so the extent to which the hemi-cellulose and lignin in these components can be broken down in the rumen will have a significant influence on the energy value of the maize silage.
“This is measured as the digestibility of the neutral detergent fibre (NDF).
Research by Oba and Allen shows that for each 5 per cent increase in NDF digestibility, intakes increase by 0.63kg, leading to a rise in average daily milk yield of an extra 0.9kg.
“Choosing one of the modern maize varieties with higher cell wall digestibility and then harvesting it at the optimum time will maximise the NDF digestibility of the silage.
“Harvesting too late not only compromises quality, but risks environmental damage to soils and water which is not acceptable.”
Most maize seed used to be treated with mesurol to protect against bird damage, but this active has been withdrawn.
Now, almost 90 per cent of maize is treated with products containing Korit.
Bird damage will not be a problem everywhere, but few growers are willing to take the risk, says Tim Richmond, maize manager UK and Ireland for LG.
He says: “Many growers will not know what the risk of bird damage is for each field and sometimes, by the time it is obvious there is a problem, it is too late.
Choosing a treated seed is often viewed as the best insurance policy.
“Korit is the most commonly used seed treatment now, but if not handled carefully, it can be a danger to human health.
Protective personal equipment, including a mask, goggles and overalls, should be worn at all times when handling it.” Mr Richmond says the key to avoiding significant bird damage is to adopt best practice at every stage to ensure the maize plant grows away quickly and vigorously so it is ‘knee high by July 4’.
He says: “Make sure to drill to the depth where soil moisture levels are adequate to ensure good seed to moisture contact and do not drill until soil temperature at seed depth has consistently reached 8-10degC.
Korit-treated seed should be drilled in a similar way to seed treated with mesurol.
Compaction “Removing all soil compaction and creating an even, fine seedbed prior to drilling when the soil is between 8-10degC will give the plants the best start and minimise the time period they are vulnerable to bird damage.
“To aid rapid establishment and to promote healthy, robust plants, LG is now offering a new, unique seed treatment, Korit Pro, which has three modes of action.
“Alongside the bird deterrent, it provides additional fungicide protection and contains trace elements which boost root development and improve crop emergence.
Sedaxane protects the plant against attack from the Rhizoctonia pathogen which causes stem and root rot, damping off and foliar blight.
This can lead to nutrient and water stress, resulting in significant field losses.
“Sedaxane helps by improving root development, which sets the foundation for higher, more consistent yields.
“Including manganese and zinc in the treatment so they are positioned close to the roots improves crop emergence and establishment through the sensitive two- to six-leaf period.
“Zinc deficiency can delay flowering and reduce plant size, increasing susceptibility to disease and ultimately a loss of yield.
Manganese is a vital element for maize growth because it has a role in enzymatic activity, chlorophyll synthesis, photosynthesis, nitrate reduction, amino acid and protein synthesis.”
Maize forms two-thirds of the forage portion of the diet for Tim Dale’s 350 all-year-round calving Holsteins, which average 10,500 litres, so he recognises the importance of a successful maize crop to his business.
He says: “As we farm on predominantly medium soils over sand and gravel, the farm tends to be drought prone, so maize is an important crop for us.
While we can grow good grass, it can be inconsistent depending on the weather.
“We need reliability in our forage production and we have been growing maize for about 30 years.” Feed quality Mr Dale currently grows about 73 hectares (180 acres) and targets a minimum yield of 12.5 tonnes of DM/ha (5t DM/acre).
He aims to harvest when DM is in the mid-30 per cent range and this figure was achieved at harvest 2020.
Mr Dale says: “We have been growing early varieties of maize for several years, as we want to harvest in good conditions to ensure we have maize to include in the diet.
“I select varieties based on a combination of DM yield to guarantee the quantity we need and feed quality as this helps drive milk production.
“To help manage risk I will usually grow a combination of varieties, especially as some of our fields are north-facing.
LG Glory has been a mainstay for many years and has performed consistently.
“In 2020 I grew some Conclusion as seed of other varieties was in short supply and it made sense to try a new variety rather than choose a longestablished option.
This year we made a total of 2,920t of maize silage at 31.8 per cent DM, giving 928t of DM, at an average of 5t DM/acre.
The Conclusion performed best of all the varieties coming in at 5.8t DM/acre and will certainly be a variety we consider for 2021.”
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