South: Prioritise herbicide use

Following our fourth rain delayed harvest on the trot, drilling is now underway in the region. With much of the oilseed rape drilled well into September it may well be necessary to apply some nitrogen in order to get the crops well enough established to go through the winter without too many problems.

At the time of writing I have already seen one rape crop devastated by rabbits. Pre-emergence herbicides are working well at the moment, but with the rapid turn around between crops, cereal volunteers are going to be a major problem. This will need dealing with early in the crop’s life to avoid unwanted competition and the sucking up of any nitrogen that might be applied to get the crop going.

Cereal planting is happening, but is always a fairly protracted affair in this part of the world as many crop follow late harvested crops such as grass and maize. Many growers in the region also worry about getting crops too proud going into the winter, particularly barley which can collapse on itself and rot if the canopy gets too large.

Most barley crops are destined to receive a pre-emergence herbicide as grassweed control post-ememergence is difficult, particularly if the variety is not tolerant to chlorotoluron.

Concern is growing over the availability of flufenacet products as this active provides the backbone of the pre-emergence programme. I am now prioritising the use of this active on the barley crop and planning to use a different approach (probably post-ememergence) on the wheats where difficult grassweeds are not a problem.

So far slugs have not been a problem. If we are to retain metaldehyde as an active ingredient we will have to hope that we do not get large slug populations in the autumn as it would appear that it is when we use large quantities of pellets that we get the spikes of active ingredient in water. The similarities between metaldehyde and IPU seem to indicate we may have a problem retaining the product even if, as an industry, we adopt a best use stewardship programme.

With at that cheery thought I will sign off and hope to report next month that drilling in the area has been successfully completed.

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