Five tips for growing spring barley on heavy land

Spring barley is an increasingly popular option among heavy land growers looking to control black-grass. Independent agronomist Andrew Cotton gives his advice for getting the best out of the crop

1. Know your market

For malting barley, whether a contract is in place or not, growers should check end user specification early in the season so agronomy can be tailored towards meeting these criteria.

Popular varieties such as Propino and Planet are readily marketed, while Irina has also become more in demand recently, Mr Cotton says.

“There are some good contracts around, so it’s worth doing your research early.”

The Maltsters Association of Great Britain (MAGB) provides information on general malting barley specifications and publishes an annual survey of reasons for loads being rejected. Common causes include ergot, small grains, nitrogen, infestation and germination.

2. Establish it well

All primary cultivations should ideally have been done in autumn, so the first and only spring cultivation is with the drill.

It is often too wet to disturb soil to depth and doing so risks bringing black-grass seed to the surface.

Minimise soil movement by using a drill with discs or low-disturbance narrow tines.

Use higher seed rates where black-grass control is the priority. Aim for 350-400 established plants/m2.

Be realistic about the likely establishment depending on field conditions and adjust seed rates accordingly - typically sow 15-20% more than the target population.

Most spring barley benefits from a single purpose seed treatment, such as Redigo Pro(prothioconazole + tebuconazole) but where wireworm is a risk it may be worth using a treatment with fungicidal and insecticidal activity as wireworm can “wreak havoc” in spring barley.

3. Early nutrition vital

Barley’s fixed number of grains per ear means it cannot compensate for poor tillering as wheat can.

Encouraging and retaining tillers with good early nutrition is therefore vital. A thick, well-tillered crop is also more competitive against weeds.

Nitrogen and phosphate (as in diammonium phosphate) are key nutrients required for early development and should be applied either at, or immediately after, drilling as a top dressing or down the spout with seed to ensure nutrients are available to young roots.

This should be accompanied with 50kg/ha of sulphur (SO3) applied pre-emergence or as soon as tramlines are visible.

Apply all remaining nitrogen by early emergence.

4. Control weeds pre-em

Limited post-emergence chemistry and herbicide resistance concerns put added importance on effective pre-emergence weed control in spring barley.

This starts with a robust glyphosate application pre-drilling. It may be necessary to use a better formulation or higher dose than in the autumn as growth is less active in early spring and weeds may be harder to kill.

A flufenacet-based pre-emergence herbicide, such as Liberator (diflufenican + flufenacet) is effective against grass weeds and can be combined with pendimethalin if required. Liberator has an Extension of Authorisation (EAMU) approval for use in spring barley.

Where black-grass or other grass weed pressure is high, Avadex (tri-allate) can also be used.

Very dry conditions can reduce pre-em efficacy, but generally it is always worth applying one given the lack of follow-up options and potential impacts of spring-emerging black-grass.

5. Protect against diseases

Rhynchosporium, net blotch and ramularia are the main disease threats in spring barley and all three have traditionally been well controlled by an application of 0.4L/ha Siltra (prothioconazole + bixafen) at T1 and T2.

However, the confirmation of ramularia resistance to SDHI chemistry in 2017, combined with previously confirmed resistance to azoles and strobilurins, means including chlorothalonil is now recommended to improve protection.

T2 is the most important timing for ramularia control, but ideally 1.0L/ha of CTL should be included at both T1 and T2.

“There are other options, but this approach is fairly straightforward and will work.”

Lodging and brackling were problems in 2017 as a result of rapid soft growth at the end of May. A low dose of trinexapac-ethyl at GS 31 or ethephon+mepiquat slightly later at GS 35-37 can help reduce the risk.