In the final article in this Maize Matters series, experts are optimistic about harvest prospects and reflect that fungicide applications will have produced a return on investment for many growers this year.
Brendan Paul of Agrii describes the crop as ‘fantastically advanced’ and predicts an early harvest for most, with cutting as early as the end of September in some areas.
“Quality may suffer slightly if we get bumper crops, but the total energy content of the maize silage should be higher, as starch tracks dry matter figures fairly closely,” says Mr Paul. “It is just as well that maize is going to fill the clamps for 2017, as grass silages have largely failed to meet expectations.”
Weed control has been excellent, he adds.
“The soil was too dry in many areas for pre-emergence herbicide applications to be effective, but post-emergence control has produced clean crops with good quality cobbing.”
Trial work on sowing cover crops simultaneously with maize seed, to avoid leaving fields bare over winter and enhance soil structure and fertility, have met with only limited success to date.
“This system is used extensively in Denmark, but the maize has out-competed the cover crop. It takes the lion’s share of soil moisture and prevents the smaller plants from accessing sunlight.”
Crops in the south west of the UK got off to a good start, according to BASF’s Andrew Clune, who reports the favourable conditions persuaded some growers to omit a fungicide application. The wet spells which followed may have left many regretting their decision.
“Maize yield losses due to fungal disease can be as high as 50 per cent, in cases of severe infestation,” says Mr Clune.
“The greatest threat is corn leaf blight, which thrives in temperatures of 16-18degC and a period of six to 18 hours of continuous wet leaf.
“There is a case for applying a fungicide to maize as a routine precaution, because the risk extends into the period where the crop is too tall for treatment. Trials have shown a fungal application on maize will improve yields, even in the absence of infection.”
John Burgess of KWS believes some of this year’s crop may suffer from ‘green snapping,’ a condition rarely observed in the UK, but common throughout continental Europe.
“Green snapping is due to stem elongation caused by a period of rapid early growth, coupled with high winds and storms, which weaken the structure,” he explains. “It can affect 10-20 per cent of the crop, although damage is mainly seen on the headlands. The plant can recover, as long as the process does not occur before tasseling. It is sometimes associated with specific varieties, but in fact it is a seasonal problem.”
Mr Burgess concurs maize will yield well this year, with the exception of crops challenged by disease. But he is not convinced that the UK will enjoy an early harvest, despite the fact that tasseling countrywide took place two weeks earlier than usual.
“The season has mimicked 2014, in some respects. We had a prolonged period of high temperatures, followed by cooler weather, so grain fill may be fairly slow,” he says.
“Dry matter content is probably going to be more difficult to judge for 2017, where we might see a relatively low grain to stover ratio because plants will have a large, green stem. I would always recommend a target dry matter of 30 per cent-plus, but crop readiness is not always easy to judge, without laboratory testing.
“Growers often over-estimate dry matter figures and this can lead to disappointments at feed-out. One fairly reliable method of determining point of harvest is to cut off the stem at about 10cm above the ground and twist it. If sap runs from the material, then dry matters will not have reached the optimum level and cutting should be delayed until virtually no sap is produced.”