Keeping the third leaf clear of septoria is the key step in all fungicide spraying programme designed for winter wheat.

This was one of the key messages delivered by Teagasc tillage specialist, Shay Phelan, at a recent spring crops walk in Co Louth.

The event was hosted by the McGuinness family, who farm near the village of Richardstown.

According to the Teagasc representative, effectively targeting ‘leaf three’ will give sufficient septoria cover through to full flag leaf emergence.

Phelan said: “But making this happens depends on growers being able to identify an emerging third leaf at the appropriate time.

“This process requires farmers taking individual wheat plants at their different growth stages and, literally, dissecting out the various leaves.

“This activity is best undertaken at a table in a farm office or kitchen, thereby giving the farmer or grower the time allowed to inspect the selected plants thoroughly.

According to Teagasc, some 80% of the yield from winter wheat comes from the top half of the canopy.

So having a good clean foundation is important. One of the key ways of achieving this is ensuring the optimum timing of fungicide applications.

“Current fungicide choices do not have the flexibility that they used to have a number of years ago, so timing on the application of different fungicides needs to be precise," Phelan said.

“Growth stage may not be an accurate indicator of the actual leaves present in the crop, so dissecting plants and identifying the correct leaf to apply the fungicide is critical for optimum performance.”

“Leaf three on many winter wheat crops will be fully emerged this week, so it is the optimum time for a T1 fungicide applications to control septoria.”

Meanwhile yellow rust has been identified within a number of winter wheat crops growing in the north-east of the country, which Phelan confirmed at the recent crop walk.

“The recent rains have significantly increased the disease pressure within all cereal crops," he said.

“Specifically, where winter wheat is concerned, we know that a combination of early sowing and wet weather at the leaf three disease can combine to increase septoria pressure.

“The variety Graham is particularly susceptible to yellow rust,” the tillage specialist added.