Surging prices should make spring weed control, even in poor crops, well worthwhile, growers are being advised.

Oilseed prices have almost doubled since last year to about £310/t for harvest 2008, says United Oilseeds’ Ian Munnery.

“This completely changes the economics of growing the crop. Anything growers can do to improve yields and protect quality will certainly pay dividends.”

Yield aside, quality is important and often overlooked.

Reducing admixture, particularly from weed seeds, lowering moisture and raising oil content can add 8-14% in premium, pushing overall crop price to over £350/t, he calculates.

Conversely, weed seeds, high moisture and low oil level lead to stiff penalties or even rejection.

“This isn’t the time to be cutting back on inputs and gambling on getting it right.”

Spring weed control should be top priority for oilseed rape, agrees Procam’s Dave Ellerton.

“Sow thistles, cleavers and mayweeds can erode both yields and harvest quality. Last year, I found Galera (clopyralid and picloram) gave excellent results in just the situation which many growers now face.”

Tom Sivewright, who grows 66ha of rape on heavy clay at Bar Farm, Longstanton, Cambridgeshire, recalls last year’s experience on three fields where sow thistle populations were 20-40/sq m.

“We treated the two worst fields with Galera. It gave 100% sow thistle control and knocked out cleavers and mayweeds. I only wish we had treated the third field by harvest it was horrendous,” he says.

The product may not be applied after the flower buds rise above the crop canopy (GS3.5).