Farmer Focus: Blackgrass not defeated, but numbers down

This time last year I talked about blackgrass raising its ugly head above the wheat. While there hasn’t been a massive change, there isn’t as much as last year.

It may be the herbicide choices we made last year of Avadex (tri-allate) at drilling, pre-emergence Trooper (flufenacet + pendimethalin)/Herold (diflufenican + flufenacet) followed by Horus (iodosulfuron + mesosulfuron) including an anti-drift agent in March.

I also made sure that the blackgrass was actively growing when I sprayed it, which for me was March by the time I could travel.

See also: Read more from our arable Farmer Focus writers

The other major difference this year has been that our worst blackgrass fields are currently under spring oats.

The blackgrass is still there and using the cover crop/spring method hasn’t defeated it, but there is a marked reduction in numbers from last year.

Having shown, although limited, improvement in our blackgrass control, we have committed to a fairly hefty fungicide programme this year with a new-generation SDHI at both T1 and T2.

Like many others, I was hoping to pull back on the fungicide programme this year with the dry weather we had.

As I was loading the sprayer and applying the T1s there was a big lump of rain on the forecast – fantastic for thirsty spring crops, but not so great for cheaper fungicide programmes.

T1 and T2 timing have been very close together this year and the gaps between our sprays have been short to say the least.

I have been wondering if I have jumped the gun and not got my money’s worth out of the T1 by spraying our T2 less than three weeks later in some cases.

The proof will, hopefully, be in the pudding, but it may leave me open to a split dose T3 just to increase protection here.

The window between T2 and harvest looks fairly long now and saving all that green leaf area should equate to yield.

That brings me neatly to grain price. With wheat price at current levels it is very easy to think of cutting corners in fungicide and blackgrass spend, as talked about above, but every tonne extra of yield gives you more chance to get a better payback.  


Robert Nightingale manages 600ha of combinable cropping across Sentry’s operations in Sussex and Surrey. Cropping includes winter wheat, oats, oilseed rape, linseed, peas and soon beans.