Under-sowing spring cereals with a perennial ryegrass ley has the potential to increase production, whilst cutting establishment costs.

That's according to Germinal’s William Fleming, who told The Scottish Farmer that livestock producers drilling spring cereals for wholecrop, or grain could gain significantly by under-sowing crops with a following grass ley.

Along with fully cashing in on the land’s production potential by minimising any barren period, the practice also takes time pressure off post-harvest when the ley would otherwise need to be established.

“Under-sowing this spring could be particularly important to producers who may be concerned about a shortage of silage or forage stocks,” he added.

As with any reseeding or establishment of a new crop, soil tests should be done in good time, he said, with attention paid to soil fertility, pH and structure. That means that the cereals which go in first must be at a slightly lower rate that 'normal' and then grass seed is drilled or broadcasted into the surface. Cereals and grass seed can both be drilled the same day, but not at the same pass, he added.

The cereal crop should be drilled at 40 to 50kg/acre (100 to 120kg/ha) at 2.5 to 4cm deep, and then rolled to prepare a fine and firm seed bed for the grass ley. Grass should then be broadcast or drilled, no deeper than 1cm.

For farms in areas where wet harvest conditions may be a concern, Mr Fleming said an under-sowing system works best when the cereal crop is taken as a wholecrop when grain is at the soft, cheesy stage.

“This can be very successful, producing 6-8 tonnes DM/ha and also gets the crop removed early on when field conditions are more likely to be suitable,” he explained.

"If crops are to be harvested by combine for a hard grain, headers need to be set higher by at least 2.5cm above the top of the grass to prevent combine clogging.

"Make sure the cereal crop isn’t creating too much shade for the grass ley below and if necessary be prepared to harvest earlier as a wholecrop silage," he advised.

This means that new grass will be available for a late silage cut by early autumn, or alternatively, it might be grazed with sheep or youngstock, to encourage the ley to tiller out and be in prime condition for the following spring.

"Always remember the main objective is to get a new grass ley established and the priority is the quality and density of the sward, so be prepared to take the cereal early if necessary to avoid damage to the ley below," he added.