Increasing populations and control failures have led Suffolk farm manager and BASF Real Results initiative member Edward Vipond to rethink his approach to managing black-grass.
Edward Vipond manages 1500 hectares of arable land for the Claas family from a base near Bury St Edmunds in Suffolk. Troston Farms’ land is spread across a radius of 24 miles and soil types that range from black breckland sand to heavy clay.
Mr Vipond’s approach to managing black-grass is strategic, long-term and pragmatic and he is clearly a manager with an eye on the future.
“Recently I realised I had probably 20 harvests left in me, so I’ve been having a period of reflection. You spend an awful lot of money [on black-grass control] but can end up feeling you are back to square one or worse [because of the rate of seed multiplication].
“Like many other farmers I’ve been relying on something in a can and those cans are being depleted; going forward they will be some of the answer but not all of the answer,” he says.
For many growers there is often a tipping point in their battle with black-grass and for Mr Vipond it came with a field of oilseed rape.
Despite being given ‘the works’ in agchem terms, including propyzamide and clethodim, the black-grass population in the crop was so high and the seed return to the following crop of wheat so vast, that Mr Vipond admits he found himself wondering what he doing.
“So last year I gave in and sprayed some of the wheat off; I’ve never done that in my life. And that was a gamechanger,” he says.
He sprayed off two hectares of the 24ha field of wheat with glyphosate. This year the field was in beans and yes, there was black-grass in the crop, but at noticeably lower levels where the preceding wheat crop had been burned off.
“You could see to a line where the black-grass had been sprayed off in the wheat crop and where it hadn’t. I will now be more ruthless with my approach,” says Mr Vipond, who last autumn started to put in place a range of measures he hopes will reduce the weed burden across the farm.
Black-grass is present across all the farm’s soil types, even on the lightest land, where Mr Vipond attributes its presence to spread via machinery.
However the most severe infestations are on the heavy land, where a lack of viable break crop options is adding to the challenge. There are 450ha of spring crops in the rotation – a little under a third of the overall acreage - but the area is not equally distributed across soil types, with the proportion of break crops lower on the heavier land.
“To add to that, I’ve pulled out of OSR on heavy land on the basis that I harvested a very healthy crop of flea beetle this year.
I spent quite a bit of time and money establishing rape to a good degree last autumn; we had some thumping rape crops in September into October, come January it wasn’t growing. This harvest we ranged in yield from 2.3t/ha to 4.5t/ha; my average was 3.55t/ha, but the potential was so much more.
“We tried forage rye for AD on the heavy land, to take a year’s black-grass seed off the farm. It sort of worked but then the black-grass in the following year’s crop made me think it didn’t. Nothing went wrong, it was just the seedbank was so huge.
“I looked at soya but I haven’t got the confidence; maize on the lighter element of the heavy land but you are at risk of seriously messing up your soil structure; I’ve grown linseed before but it doesn’t fill me with confidence; peas are not great in the same rotation as beans.
“In place of OSR we are growing winter barley, which is going to make the black-grass even more challenging. My white straw percentage is just going up and up.”
While solving the heavy land break conundrum remains a serious challenge, he has implemented a number of actions around cultivations, drilling dates, seed rates, autumn herbicide programmes and crop destruction if necessary.
“I try and plan my cultivations strategy ahead. How am I going to fit in the cultural control? What is the cropping for the next three to four years? What are the jigsaw pieces I need to put together?
“I am now in a rotation where there will be beans, two wheats and a ‘what if’ but I know exactly what I am doing cultivation-wise because I want that black-grass seed on top.
“I won’t plough heavy land or for beans; I will min-till or deep tine till for beans.
“The plough is not redundant on the heavy land but it won’t be used unless absolutely necessary. With ploughing, I am not confident that we are not bringing up fresh seed. It hasn’t just arrived this black-grass, it has been around for a while. So I am keeping the seed that is down [the soil profile], down and using min-till to keep the fresh seed on top.”
Winter wheat drilling dates have been pushed back.
“We were a month later starting drilling [in autumn 2018] than we were the year before, starting on October 17 at 325-350 seeds/sq.m and not being afraid to increase that,” says Mr Vipond.
“I have to go this late on my heavier land although it is not a choice I am particularly comfortable with. My heavy lands fields that I know I have a problem with will be in a 70% seedbed as soon as I can; we’ll get in there quick, cultivate, then leave them alone, spray them off once, possibly twice with Roundup and then pick our moment.
“I have got 480ha of wheat to go in the ground this autumn. Some of it I haven’t got black-grass on and would be happy to drill in the first week of October. And then it is a case of where is my worst black-grass field, where are my priorities, how brave do I feel? I want to be drilling most of my non-root cropped land in October.
“I think you have got to look at your seedbeds, look at the weather in October, look at how much of a black-grass flush you have had. And if there is no flush at all and you really feel brave, leave it alone and put spring barley in it; it doesn't have to be a wheat crop.”
In addition Mr Vipond has opted for what he describes as a “robust and fairly ruthless” pre-emergence herbicide stack, comprising Crystal+DFF (flufenacet+pendimathalin+DFF) pre-emergence followed by peri-emergence Avadex (triallate), applied as the tramlines become visible, and post-emergence Atlantis (iodosulfuron+mesosulfron)+Liberator (flufenacet+DFF).
“And it [Atlantis] will be autumn-applied, not spring-applied because once you leave it until the spring you have lost the battle, the black-grass is far too big.”
And the decision to apply glyphosate to areas of a crop that are too badly infested will most likely be made pre-Christmas, but will be made on gut feeling, rather than any weed count threshold.
“You’ve got to swallow the bitter pill of putting your pre-ems on, that’s got to happen. But you don’t want to be spending money on fungicides and nitrogen.
“What do they say – 96% control to stand still? This year I might have got into the 90%s in my wheat crop. I think it is a gut feeling and being thorough enough when you are crop walking,” says Mr Vipond.