West: Good spraying weather required

Given the wet and windy weather outside, I am glad to be in the office writing this blog. Fortunately, drilling was completed sometime ago, with later drilled crops now emerging.

Slug problems this autumn have not been too bad and, as a result, fewer pellets have been used, which has to be good news.

The occasional spray miss (control plot) has served to show how well pre-emergence herbicides have worked in winter cereals. There has, however, been more crop effect from pre-em’s than we have seen for a few years. Excessive rainfall shortly after application, capped soils, and the high loading of chemicals we are applying are responsible for this damage.

A concerted effort is being made to apply Atlantis (mesosulfuron + iodosulfuron) in the autumn, but conditions do need to be ideal. Remember that spray quality, forward speed, etc, are vital to maximise product efficacy.

A handful of fields where populations of blackgrass were high and plants nearing the 3-leaf stage have just received Atlantis. The majority of fields where Atlantis has been recommended are ready for treatment about now, just as the weather deteriorates.

Oilseed rape crops have continued to grow over the past fortnight. In hindsight, some crops should have received a fungicide with growth regulator activity. But it is now too late for these treatments to be effective.

There is much debate as to the timing of propzyamide or carbetamide applications for blackgrass control in oilseed rape. It looks like soil moisture conditions will be met this week, but my view is that soils still need to cool down a bit. The concern is that in the meantime blackgrass is getting ever bigger. The other problem will be getting these residual herbicides onto the soil in crops with big canopies.

On many farms, spring cropping is a vital tool in the fight against grass weeds. In order to make the most of this opportunity, careful consideration needs to given to cultivation choice and timing. Consider glyphosate applications as soon as possible, ploughing pre-Christmas, and a glyphosate application before drilling in the spring.

See more