MANY CEREAL growers should be able to save money on grassweed control this spring, but field-by-field assessment is vital to avoid future trouble.

Autumn herbicide treatments have performed unexpectedly well, offering scope to wait to see whether spring applications are really necessary, say independent advisers.

Much depends on programmes already used, says TAG’s Notts-based Andrew Wells. “We are finding that what was applied in November and December has worked very well. Pre-emergence and even post-emergence treatments have done a surprisingly good job.”

The main dilemma lies with blackgrass and ryegrass, where many growers will be looking to Atlantis as the main spring weapon.

“In general people still want clean crops, and it is difficult to walk fields and be sure you haven’t missed patches. So they tend to err on the side of caution, but are increasingly looking at their spending.”

For growers who used a cheap holding approach, based for example on isoproturon (IPU) and trifluralin, it is relatively easy to justify Atlantis, which with its BioPower wetter costs about £31/ha (£12.50/acre), he says.

But those who applied a more robust programme, say of pre-emergence Crystal, Ice or Trooper followed by post-em IPU, costing about £46/ha (£18.60/acre) in total, should assess the need for a follow-up more carefully, he suggests.

“Where they have already spent serious money they are unwilling to spend nearly as much again.”

Trimming the dose of Atlantis overall from the full recommended 0.4 1itres/ha could be false economy, he warns. “You must get control. If you use a three-quarter dose and it doesn’t work it could cost you.”

Members of the Association of Independent Crop Consultants agree there are savings to be made.

Autumn herbicides, including Atlantis, have worked exceptionally well, says Lincs-based Ruth East. “My clients are very selective with Crystal, using it only where they are expecting bad blackgrass.

“Where we had low levels we used IPU, Treflan, Uranus or Stomp, knowing that where we hadn’t had an expensive programme we would probably have to go later with Atlantis. But not every field will want a spring treatment.”

She is also prepared to try reduced Atlantis doses. “I”ve seen trials where 0.3litres/ha has done as good a job as 0.4.”

There is scope to cut the dose but not where there are wild oats or resistant blackgrass, warns Bridget Carroll from the same county.

andrew.blake@rbi.co.uk