Supplies of key pre-emergence herbicides Crystal and Liberator are failing to meet demand, forcing some growers to settle for inadequate weed control programmes.

It means some farmers with troublesome grassweeds won’t be able to apply a robust pre-emergence spray, says Norfolk agronomist Andrew Watson.

“If you haven’t got Crystal (pendimethalin + flufenacet) or Liberator (diflufenican + flufenacet) you’re stuffed. If you’ve got resistant grassweeds you need these products to get enough flufenacet to achieve adequate control.

“Without them you have to rely increasingly on Atlantis (iodosulfuron), which is bad policy and heightens the risk of resistance build-up.”

It is up to manufacturers to ensure there is sufficient product to meet demand, he says. “Slightly more wheat is in the ground than predicted, but demand for these products is not much higher than in a typical year – they just haven’t produced enough. They ask us to support R&D products and in return they should ensure there is enough to go around.”

But BASF says increased demand as a result of high blackgrass pressure is the main reason for the shortage. “We have had unprecedented demand, which we are struggling to meet,” says cereal herbicide product manager Sarah Mountford-Smith.

But when asked by Farmers Weekly if supply was lower than previous years, she declined to comment. “Growers should contact suppliers for the latest position and discuss alternative options with their advisers.”

Crystal should be reserved for fields with the worst grassweed problems and other areas should be treated with alternative products, she says. “We have alternative pendimethalin products, which can be mixed with other chemicals to control a number of weeds.”

Chris Cooksley, combinable herbicides campaign manager for Liberator manufacturer, Bayer CropScience said: “We’ve brought in everything we agreed, but demand is high and we are trying to bring in more product if we can. Hopefully we will have some additional supply for October and we have ramped up our autumn Atlantis supply.”

Agrovista agronomist Swaran Bachoo says the firm is “seriously short” of their own-branded Crystal variant, Trooper. “On average, our agronomists will be 50-60% down and we’ve had to restructure our plans. It took me nearly two days to work out how I was going to deal with it.”

He reckons growers with bad grassweed problems could end up spending an extra £12.50/ha on alternative products to achieve the desired level of control. “We might have to come back with a mid-season application, which is something we don’t normally do, and we might use Atlantis later in the autumn.”

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