Round Up Resistant Blackgrass

[Wheatseeker]

I had one field very much like that, gave it 1.5ltrs/ha in ideal conditions, and result was the same as your picture shows, went in again with 3ltr/ha and have had a fantastic kill needless to say it`ll be a Spring sown crop going in, hoping to get another flush or two out of it before drilling mind. Result of buggering about when it was in OSR last year, taking it through to harvest when I should have sprayed the lot out and put SB in it`s place.

Exact same scenario. Would also expect higher rate to work, but just wanted to experiment and see exactly where we are with it as we usually stir it up and drill after a stale seedbed.

 

[Wheatseeker]

That's
some serious stuff, what are you planning to drill in the spring in that field?

Not entirely sure yet! Was going for a spring cereal, but now thinking of fallow.

 

[Baling Hay]

What a crop not be better than fallow to at least provide some competition? This constant round upping for a year may only make things worse long term?

 

[Andy26]

Not entirely sure yet! Was going for a spring cereal, but now thinking of fallow.

I have a field similar not quite that, only it was Fallow last year too!

I think somethings telling me it should really be a meadow! But will see if a few more stale seedbeds and Spring Barley may work.

 

[Wheatseeker]

So what % of those plants would you say were there before spraying? I would be very upset if my agronomist had suggested such a low dose of Roundup. Personally I think 1000g/ai per hectare is the minimum.

40-50%

Agree on the dose but wanted to find out how much is really needed.

 

[Wheatseeker]

What a crop not be better than fallow to at least provide some competition? This constant round upping for a year may only make things worse long term?

Along with constant cultivations it should help.

 

[yellow belly]

if round up fails check the water quality and cleanliness also jets and droplet fineness
as well as the weather in the 24 hours after application round up is the least rainfast spray we use

in setaside wet muddy tramlines recovered from roundup but the second application took out all the bg

non grass weeds take a lot of killing by round up such as cranes bill and rose bay willow herb 3litres not enough in some cases especially in wet conditions

 

[Green oak]

There's a lot of fuss on which nozzle what rate of water and best speed to go when spraying one leaf blackgrass with Atlantis but when it comes to one leaf blackgrass with round up there's to many variables. Plenty of product plenty of water and water conditioner.

 

[Andrew K]

There's a lot of fuss on which nozzle what rate of water and best speed to go when spraying one leaf blackgrass with Atlantis but when it comes to one leaf blackgrass with round up there's to many variables. Plenty of product plenty of water and water conditioner.

Less speed, angled nozzles, dry leaf works well on both jobs IMO.

 

[SilliamWhale]

if round up fails check the water quality and cleanliness also jets and droplet fineness
as well as the weather in the 24 hours after application round up is the least rainfast spray we use

in setaside wet muddy tramlines recovered from roundup but the second application took out all the bg

non grass weeds take a lot of killing by round up such as cranes bill and rose bay willow herb 3litres not enough in some cases especially in wet conditions

Have you ever tank mixed a contact with roundup to kill these two little buggers?

 

[EJS]

40-50%

Agree on the dose but wanted to find out how much is really needed.

I had very similar scenario, 1.5L of generic only killed about 20-30%, it knocked most of it but seemed to grow out, but 2L did 100% job, will not go in again with less. At least I know now though, having always been advised 1.5L, haven't found a noticeable effect of water conditioner, but interested in anyone who has?

 

[Robigus]

If you were going to fallow would it not be better to cultivate rather than repeat spray?
Plough/mintill or what ever, then knock up a bloody great set of old zig-zag harrows and run over it repeatedly whenever you see anything germinating.

 

[warksfarmer]

Cant believe what some people are doing. Clearly across the country grass weeds and in particular blackgrass is a major issue. Its getting worse so the chemical attack is not working!! so why keep throwing chemicals at the problem and then still having the problem.

I just think that peoples current approach of:

• stale seedbed at least x 1 but sometimes x 2
• pre em
• autumn herb
• spring herb
• pre harvest desiccate

Is to scary to continue with. Its costing an awful lot of money and will lead to resistance for sure.

 

[Baling Hay]

Cant believe what some people are doing. Clearly across the country grass weeds and in particular blackgrass is a major issue. Its getting worse so the chemical attack is not working!! so why keep throwing chemicals at the problem and then still having the problem.

I just think that peoples current approach of:

• stale seedbed at least x 1 but sometimes x 2
• pre em
• autumn herb
• spring herb
• pre harvest desiccate

Is to scary to continue with. Its costing an awful lot of money and will lead to resistance for sure.

Like x 1000!

 

[rob1]

Cant believe what some people are doing. Clearly across the country grass weeds and in particular blackgrass is a major issue. Its getting worse so the chemical attack is not working!! so why keep throwing chemicals at the problem and then still having the problem.

I just think that peoples current approach of:

• stale seedbed at least x 1 but sometimes x 2
• pre em
• autumn herb
• spring herb
• pre harvest desiccate

Is to scary to continue with. Its costing an awful lot of money and will lead to resistance for sure.

Agree in many ways, so whats the solution apart from grassing some down, not sure the control in spring crops is that good

 

[Andy26]

An article on Fwi today, quoting Agrii's head of agronomoy saying once a farm has started to get Atlantis resistance, the control offered is just 25-30%.

http://www.fwi.co.uk/articles/06/11/2013/141853/blackgrass-sprays-need-a-residual-partner.htm

I'm not sure % control is a good way of expressing this. The seed return from just one or two resistant black-grass plants per m2 is still going to be massive even if that was 99% control.

All you've now done is selected out an even greater resistant population.

 

[Andy26]

What is sure, is that Atlantis made arable farming relatively easy from 2003-2009/10 ish.

Its a different world now.

 

[Robigus]

What were the very first chemical controls for blackgrass? I'm sure they would be illegal now but if there were a product that had not been used for decades they may be effective now, you can select susceptibility as well as resistance.

 

[Tractor Boy]

What were the very first chemical controls for blackgrass? I'm sure they would be illegal now but if there were a product that had not been used for decades they may be effective now, you can select susceptibility as well as resistance.

I'm afraid it's not that long ago. I think it was in the 80's when the first products for grassweeds in cereals came along wasn't it? Think they were the triazines( simazine,cyanazine) and IPU and CTU. Also Trifluralin and Terbutryn. Most of these only stopped being used in the last 10 years!! For break crops the oldest grassweed killers are still being used!

 

[franklin]

What's the sub-lethal dose for metribuzin on wheat?

The thing with the triazines, IPU, terbutryn, is that they are still broadly soil acting - it is the lack of effective contact sprays in cereals, but also in other crops that is causing me the most issues.

Agree in many ways, so whats the solution apart from grassing some down, not sure the control in spring crops is that good

In many ways I find spring control worse as you are relying on a residual that needs moisture which it is less likely to get, and contacts that are fops and dims.

Yes, the answer is grass.