Teagasc will host a cover crops open day at its Oak Park research centre in Co. Carlow on Friday, October 30, profiling trial results from 28 individual cover crop species established using a range of techniques and sowing dates.

The trials, run by Teagasc in association with malting group Boortmalt, examine what cover crops can deliver in spring barley-based production systems. The measured benefits include improvements in soil health, a significant reduction in nitrate leaching rates from soils, and improved levels of carbon assimilation within soils.

Michael Hennessy, head of Teagasc's Crops Knowledge Transfer Department, said visitors will see the full trial portfolio first-hand.

"On the day, visitors will have the opportunity of viewing 28 individual cover crops species, established using a range of different techniques, sown out at differing times," he said.

"The event will also profile a range of issues relating to soil health and quality."

Why spring barley is the priority

Hennessy explained that the role for cover crops within spring cereal systems has been identified as a research and development priority for a specific agronomic reason: the calendar.

"Chief among these is the fact that the likes of spring barley has a mid-August harvest date with, invariably, straw lifted towards the end of that month," he said.

"Up to now, this would have left growers with quite a narrow window within which to get cover crops established."

Spring barley growers typically clear the combine in mid-August and bale straw by the end of the month. That leaves only a short stretch of suitable weather before soils cool and establishment windows close.

Three establishment timings

To widen that window, Teagasc has tested a new range of establishment options that allow planting of cover crops pre-harvest, on the day of harvest and post-harvest.

"We have used drones to spread seed through a barley crop prior to harvest," said Hennessy. "Other options in this regard include the use of bespoke planting machines and amended fertiliser sowers."

For sowing at harvest itself, the approach is mechanical rather than aerial.

"When it comes to sowing cover crops as a spring cereal is actually harvested, it's a case of connecting a bespoke planter to the combine with the seeds deposited on the soil as the machine travels through the field," Hennessy said.

Examples of all this work will be on view at the open day.

A testing season

The Oak Park plots will also carry a practical lesson from the season just gone. Planting conditions for cover crops were "very challenging" throughout the entire month of August, according to Teagasc.

For growers weighing establishment strategies, seeing how the different species and techniques performed under poor August conditions is arguably the most valuable part of the event.

The open day also underlines the growing role of drones as a flexible management tool within the tillage sector. Teagasc expects the scope of this activity to continue expanding as the technology becomes more widely available.

Financial support for the establishment of cover crops is available to Irish growers through the ACRES and Water European Innovation Partnership (EIP) schemes.

Growers planning to attend should note the date: Friday, October 30, at Oak Park, Co. Carlow.