Forage maize in northern areas and those with less heat units are now reaching full maturity, reports Neil Groom, technical manager for Grainseed.
Brian Metcalfe at Leyburn in North Yorkshire agrees. “We thought dry matters would have been higher last week since the cob is nearly fully mature, but rain just before sampling probably dropped the dry matter recorded last week. Once we get a weather window we will harvest crops.”
Maize eyespot is widespread this year, says Mr Groom. “Eyespot has moved rapidly across the country in favourable conditions and many crops have lesions that have a 1mm dead centre surrounded by a yellow halo when the leaf is held up to the light.”
Prevention of re-infection for next year’s crop is important with so much innoculum around and action starts now. “If possible, rotate fields around the farm, plough all infected fields now and write in next year’s diary to spray a fungicide in July to protect the green leaf”.
“The Maize Growers Association has done some good work on looking at different fungicides and assessing the level of physical damage caused by the sprayer and it’s clear that it’s well worth doing when the risk is high of getting eyespot in the crop”.
As autumn progresses, the risk of frost damage increases. It’s the degree of frosting that matters on crops, says Mr Groom. “If it’s just the top 2 or 3 leaves then don’t worry about it, but when the leaves below the cob are frosted then get the crop chopped and in the clamp. The problem with frosted crops is that yeasts and moulds grow on the dead leaves and these can cause mycotoxins to be present in the silage at feeding”.