blackgrass resistant to Glyphosate!?!

[Kryten]

We have a field planted late with spring linseed - linseed doing fine; went with 3 litres of glyphosate plus gly-fast in 180 litres of water prior to drilling but had to go twice as half the field was too wet to travel nicely.
Yesterday, walking over, where we went the first time the kill is complete but the later spray (about a week later) has had little if any effect on the blackgrass. Has anyone else had evidence of resistance?

 

[Gong Farmer]

If the later treated stuff had reached its stem extension phase it would have shrugged off the glyphosate. Used to happen often in set-aside years.

 

[Nick.]

I’ve done some cover crops at 4l plus Xchange.
There’s a lot of BG it hasn’t killed.
I was thinking I’d gone too late (growth stage).
It’s worrying that’s for sure.

 

[Flat 10]

If the later treated stuff had reached its stem extension phase it would have shrugged off the glyphosate. Used to happen often in set-aside years.

This is what I was talking about @Feldspar . I know not applicable but just for interest.

 

[Kryten]

If the later treated stuff had reached its stem extension phase it would have shrugged off the glyphosate. Used to happen often in set-aside years.

That's interesting and perhaps a little reassuring. Thanks

 

[Flat 10]

It does (certainly used to) mention this on glyphosate labels.........
makes you wonder if anyone actually reads them..........

 

[Badshot]

I applied it with some liquid fert in the mix.
Now that really makes it work ..

 

[Laggard]

I applied it with some liquid fert in the mix.
Now that really makes it work ..

How much liquid fert?

 

[Badshot]

How much liquid fert?

It varied.
Some had 50litres to 150litres water.
Some had 150litres to 50litres water.
It all worked very well.
Used it to get some n in the seedbed. Gave the crop a nice kick start.

 

[Right-arm fast]

We have a field planted late with spring linseed - linseed doing fine; went with 3 litres of glyphosate plus gly-fast in 180 litres of water prior to drilling but had to go twice as half the field was too wet to travel nicely.
Yesterday, walking over, where we went the first time the kill is complete but the later spray (about a week later) has had little if any effect on the blackgrass. Has anyone else had evidence of resistance?

We had exactly the same scenario in a field. The bg etc had got quite thick as it had been left too long by the time it dried to get on and spray. We applied 2l of gly plus wetter @ 200l/ha twice. The second time driving the tramlines back in the opposite direction as I thought we might struggle kill all the plants in one application as some nearly had seed heads out so running out of time. This was an over wintered stubble.

 

[Feldspar]

If the later treated stuff had reached its stem extension phase it would have shrugged off the glyphosate. Used to happen often in set-aside years.

My plan is to have quite a bit of Mid Tier extended over-winter stubble which can only be sprayed off from 15 May. Have had this option now for quite a number of years and hadn't seen a problem. Have a bit we have done this year which is less than 100% convincing. Could it be the tallow-amine? Are there any tricks to enhance effectiveness?

 

[B'o'B]

My plan is to have quite a bit of Mid Tier extended over-winter stubble which can only be sprayed off from 15 May. Have had this option now for quite a number of years and hadn't seen a problem. Have a bit we have done this year which is less than 100% convincing. Could it be the tallow-amine? Are there any tricks to enhance effectiveness?

The removal of tallow-amine has really reduced the reliability of generic glyphosate. I have taken to using x-change @ 0.25L /100L water then adding Li700 also at the same rate.
I add the x-change as I start filling the tank but only add the Li700 once the tank is almost full so hopefully the x-change has done its job. I then add the glyphosate using the conditioned water through the induction hopper before topping up the last 100-200L clean water. It may be overkill but it seems to work.
First time out using non-tallow glyphosate @4 L/Ha + Marlin in very good conditions resulted in an incomplete kill of rape stubble so I knew I had to do something to get it working better as you can’t mess about if you’re no-till!

 

[MNBVCXZ]

Drop out the x-change? Li 700 is also a water conditioner?!

 

[B'o'B]

Drop out the x-change? Li 700 is also a water conditioner?!

Different ways of working I think though. I’m off to @drummer_bruhaha Aduvant academy next week so I’ll know more then. To be fair I not very fussy about the rate of x-change when filling, but we are in quite a hard water area so don’t want to take a chance on that

 

[Nick.]

Drop out the x-change? Li 700 is also a water conditioner?!

I’ve wondered this too.
But when I have used both it seems to work very well and quickly.
Maybe @drummer_bruhaha could clarify.

 

[Desangosse Ltd]

Very interesting this approach. X-Change and Li 700 work in different ways. You will get some water conditioning from Li 700, but true cation lock up comes from the X-Change. Li 700 will add penetration and translocation of the glyphosate which you wont get from X-Change. The addition of both products could be described as belt and braces.

 

[Brisel]

Very interesting this approach. X-Change and Li 700 work in different ways. You will get some water conditioning from Li 700, but true cation lock up comes from the X-Change. Li 700 will add penetration and translocation of the glyphosate which you wont get from X-Change. The addition of both products could be described as belt and braces.

So a part dose of both in the tank might cover both bases? For waxy cuticles on weeds like hardened osr volunteers or thistles this might be a reasonable brew? The LI700 is an acid surfactant so I guess the water will have a nice low pH.

Taking the opposite view, you wouldn't want the adjuvants to stress the target and reduce the glyphosate uptake!

 

[Tom H]

I've not read the thread fully but I guess it because it was in stem extension. 4l/ha with a aquascope type product normally will sort it though.

 

[Desangosse Ltd]

So a part dose of both in the tank might cover both bases? For waxy cuticles on weeds like hardened osr volunteers or thistles this might be a reasonable brew? The LI700 is an acid surfactant so I guess the water will have a nice low pH.

Taking the opposite view, you wouldn't want the adjuvants to stress the target and reduce the glyphosate uptake!

You could in theory reduce the X-Change to save a few pennies, as you are getting some water conditioning from the Li700. I wouldn’t tinker with the Li700.

 

[yellow belly]

We have a field planted late with spring linseed - linseed doing fine; went with 3 litres of glyphosate plus gly-fast in 180 litres of water prior to drilling but had to go twice as half the field was too wet to travel nicely.
Yesterday, walking over, where we went the first time the kill is complete but the later spray (about a week later) has had little if any effect on the blackgrass. Has anyone else had evidence of resistance?

this is normal once the bg has reached stem extension
do the same bg at flowering stage and the kill will be complete
this also happens with most grasses, wheat as well