Teagasc is reporting quite high levels of mildew infestations in a number of winter cereal crops.
“Generally speaking, both wheat and barley crops have wintered well. Plant and tiller numbers are high in most cases,” said Marianne Mulhall, Tillage Advisor in Teagasc’s Kilkenny office.
“Normally, there is no need to apply a first fungicide treatment to barley crops until the end of March. But where mildew is attacking newly-formed leaves, a case can be made to go in that little bit earlier and to include a mildewcide in the tank mix.
There is absolutely no need for concern if mildew is attacking older leaves that will die off. The mildew may also act to kill off a number of tillers that are excess to requirements when it comes to determining final crop yields.
Mulhall said that barley crops should receive their first dressing of nitrogen over the coming two weeks.
“A nitrogen application of 50kg/ha will suffice at this stage. This is as much as crops can utilise, while still in their vegetative state. Loadings above the 50kg level will lead to nitrogen losses. Research has shown that there is no yield benefit to be gained by applying nitrogen to cereal crops before the beginning of March.
“But, conversely, there is no evidence to suggest that going ahead with a nitrogen application that little bit earlier does anything to detract from the overall yields obtained.
“Growers should also apply P & K to barley crops now. Dressings should be in line with soil test results. A crop of winter barley will remove 38kg of P and 100kg of K per hectare. These figures are based on a projected yield of 10t/ha.”
The Tillage Advisor added that grass and broadleaf herbicides should be applied to winter cereal crops before the middle of March.
“Most crops received a herbicide treatment last autumn,” she said.
“There is only one herbicide that can be used to tackle grassland weeds in barley. But there is a slightly greater selection available, where wheat crops are concerned.