How late glyphosate before crop emergence?

[DrWazzock]

Anybody any experience of applying glyphosate post drilling and had a problem due to it catching the emerging crop?
I have done a couple of acres of beet as a trial just before the seedlings break through the surface in a particularly weedy patch so I guess I’ll soon know but just wondered if folk had any experiences good or bad.
As herbicide options become ever more limited I reckon it could be a useful tool but obviously there is a trade off between going too early and missing a lot of small weeds and going too late and killing the crop. Personally I think it’s a waste of time the day after drilling.

 

[Farmer Roy]

Err, we are happy to spray right up to emergence, but if ANY cotyledons are showing, it’s a no go . . .

 

[Matt77]

Drilled my beans straight into grass last year, weather/work load stopped me spraying the grass off until the beans were up but still folded over, tipped them a bit but they all up and alive at mo, I know a bean a bit different to a cereal.

 

[DrWazzock]

Drilled my beans straight into grass last year, weather/work load stopped me spraying the grass off until the beans were up but still folded over, tipped them a bit but they all up and alive at mo, I know a bean a bit different to a cereal.

That’s later than I’d dare risk.

 

[Matt77]

I won’t lie, I had sleepless nights! but I also couldn’t bring myself to leave the fast growing rye grass as a companion crop!!!

 

[Bogweevil]

Just before crop emergence - you get to know when but I advise newbies to cover a small area with clear plastic - once braird appears under plastic it is time to go as rest of crop will be close behind

 

[Matt77]

They've had their feet wet most of the winter which hasn't helped but this is one field of the bean's

 

[deleted user 837354]

They've had their feet wet most of the winter which hasn't helped but this is one field of the bean's

Direct drilled into grass? Looks amazing.

 

[Matt77]

Yep, strip till drill, 1inch boot, wanted to drill it on the green so it passed through the drill well, had issues before with a dead mat on the top, this worked well, just a shame the weather turned immediately after drilling.

 

[Lowland1]

I do potatoes just before emergence and even if a few are poking through they seem to shrug it off. I’ve done maize however and even if you can’t see any seedlings emerging it seems to stunt the crop.

 

[DrWazzock]

I do potatoes just before emergence and even if a few are poking through they seem to shrug it off. I’ve done maize however and even if you can’t see any seedlings emerging it seems to stunt the crop.

I do wonder if there is some residual effect, despite it being said that it is broken down on contact with the soil. It won’t be instantaneous breakdown and so I think very susceptible plants could be damaged as they push through.
I sprayed off spring barley infested ploughing in November and it stayed clean as a whistle right through till we drilled in March.

 

[DrWazzock]

Half life in the soil possibly 47 days according to a bit of Googling. Makes me wonder. It could be useful or not.

 

[solo]

I nervously sprayed ryegrass off in an emerging crop of wheat as the cotyledons were just emerging. 24 hours later would have been too late according to the agronomist. It worked extremely well and the wheat grew on fine with the ryegrass issue sorted. I wouldn’t want to do it routinely as you could easily get the timing wrong.

 

[4course]

Just before crop emergence - you get to know when but I advise newbies to cover a small area with clear plastic - once braird appears under plastic it is time to go as rest of crop will be close behind

an excellent tip ,thankyou now just got to hold the plastic down in this wind

 

[BRBX]

We have one agronomist that likes roundup in with pre ems and another that wont entertain it.

 

[4course]

We have one agronomist that likes roundup in with pre ems and another that wont entertain it.

Which one s advice do you follow?

 

[yellow belly]

the day before the leaf breaks through the coleoptile in cereals
half a day later is too late

i have done cereals 11 days post drilling when it is slow emerging
this windy weather will take us down to the wire

often the first emerged plants make up less than 10%of the final plants so if you use a robust seed rate knocking them off is not too serious
especially if bg has emerged on the surface
i find surface emerged black grass is a few days ahead of the cereal seed and is killed by the well timed glyphosate

 

[Lowland1]

One thing we have found is that crop establishment can be affected by the toxins given off by decaying root matter after spraying roundup especially if you are trying to kill twitch or sedge type grasses.

 

[BRBX]

Which one s advice do you follow?

Both for the bits they look after , ive not seen any detriment to crop from using it but one of them is adamant not to so thats what we do.
Some people spray blackgrass out of beans now relying on tbe waxy leaf to save the the bean , i wouldnt be brave enough for that but I have seen it work.

 

[robbie]

I've seen trials that showed increased efficiency from the inclusion of glypho even in the absence of and weeds.

Also I was told the coleoptile doesn't absorb anything so as long as the leaf hasn't broke out it's ok to spray, it's a very fine line.