In my sprayer I have some diluted Rosate 360 TF according to
instructions, left over from last year. Will it still work this year
please, or do I need to make up a fresh batch?

Chris Hogg explained :
On Sat, 24 Apr 2021 13:47:06 +0100, Harry Bloomfield, Esq.
wrote:

In my sprayer I have some diluted Rosate 360 TF according to
instructions, left over from last year. Will it still work this year
please, or do I need to make up a fresh batch?

It's basically glyphosate, so should be OK. But you've nothing to lose
apart from the time spent re-spraying with fresh if the old stuff
doesn't work.

Ta!

Harry Bloomfield wrote:

In my sprayer I have some diluted Rosate 360 TF according to
instructions, left over from last year. Will it still work this year
please, or do I need to make up a fresh batch?

I had a sprayer half-full of diluted glyphosate that had been sitting
over winter, I also wondered if the active ingredients might have
degenerated, sprayed the weeds on Monday and they're looking very dead
already.

Chris Hogg wrote:

Harry Bloomfield wrote:

In my sprayer I have some diluted Rosate 360 TF according to
instructions, left over from last year. Will it still work this
year please, or do I need to make up a fresh batch?

It's basically glyphosate

Thinking about it, the ready to use trigger sprays of Roundup will will
sit on the shelf for many months at a similar dilution ...

On 24/04/2021 14:58, Andy Burns wrote:
Chris Hogg wrote:

Harry Bloomfield wrote:

In my sprayer I have some diluted Rosate 360 TF according to
instructions, left over from last year. Will it still work this
year please, or do I need to make up a fresh batch?

It's basically glyphosate

Thinking about it, the ready to use trigger sprays of Roundup will will
sit on the shelf for many months at a similar dilution ...

Yup. I've just finished off one such which must be at least a couple of
years old and it still worked. A bit slow, but that was in a cold snap
when nothing was growing much.

On 24/04/2021 14:52, Andy Burns wrote:
Harry Bloomfield wrote:

In my sprayer I have some diluted Rosate 360 TF according to
instructions, left over from last year. Will it still work this year
please, or do I need to make up a fresh batch?

I had a sprayer half-full of diluted glyphosate that had been sitting
over winter, I also wondered if the active ingredients might have
degenerated, sprayed the weeds on Monday and they're looking very dead
already.

Is that "glyphosate" the active ingredient or glyphosate the brand?
The two are sadly no longer the same

Proper glyphosate kills green plants by screwing up a key part of their
photosynthetic pathway and they turn a characteristic orangy yellow
after 1 to 2 weeks from application. Stone dead at three weeks. I don't
normally expect to see proper glyphosate at standard dilution take
effect within the first week. Sometimes I use it more dilute to allow
time for translocation into weeds with extensive roots like ground elder.

Unfortunately there are now branded "glyphosate" products on offer with
all sorts of other active ingredients in to make them faster acting for
the consumer market.

I suspect it will lose some activity when stored diluted in oxygenated
water but it is more the pesticides and fungicides that degrade rapidly
by hydrolysis that need to be used immediately after dilution.

--
Regards,
Martin Brown

Martin Brown wrote:

Is that "glyphosate" the active ingredient or glyphosate the brand?
The two are sadly no longer the same

I always thought glyphosate was the chemical name and RoundUp the
original brand name containing it? Mine is Gallup Hi-Activ 490g/l

Though I'm aware they now sell "vegan friendly" RoundUp possibly with
salt and/or vinegar as the active ingredients?

So I can see how you get non-glyphosate RoundUp, but how can you have
non-glyphosate glyphosate?

Proper glyphosate kills green plants by screwing up a key part of their
photosynthetic pathway and they turn a characteristic orangy yellow
after 1 to 2 weeks from application. Stone dead at three weeks. I don't
normally expect to see proper glyphosate at standard dilution take
effect within the first week.

I was quite surprised how quickly it acted, especially when I was
thinking it might have reduced effect due to age, though it was very
sunny after applying so take-up would be good, it varies per weed type,
the dandelions and docks are all shrivelled and going crispy, some of
the grasses, chickweed and the nettles are merely a bit yellow.

In message , Martin Brown
writes
On 24/04/2021 14:52, Andy Burns wrote:
Harry Bloomfield wrote:

In my sprayer I have some diluted Rosate 360 TF according to
instructions, left over from last year. Will it still work this year
please, or do I need to make up a fresh batch?
I had a sprayer half-full of diluted glyphosate that had been
sitting over winter, I also wondered if the active ingredients might
have degenerated, sprayed the weeds on Monday and they're looking very
dead already.

Is that "glyphosate" the active ingredient or glyphosate the brand?
The two are sadly no longer the same

Proper glyphosate kills green plants by screwing up a key part of their
photosynthetic pathway and they turn a characteristic orangy yellow
after 1 to 2 weeks from application. Stone dead at three weeks. I don't
normally expect to see proper glyphosate at standard dilution take
effect within the first week. Sometimes I use it more dilute to allow
time for translocation into weeds with extensive roots like ground elder.

Unfortunately there are now branded "glyphosate" products on offer with
all sorts of other active ingredients in to make them faster acting for
the consumer market.

I suspect it will lose some activity when stored diluted in oxygenated
water but it is more the pesticides and fungicides that degrade rapidly
by hydrolysis that need to be used immediately after dilution.




--
Tim Lamb

Andy Burns wrote:

Though I'm aware they now sell "vegan friendly" RoundUp possibly with
salt and/or vinegar as the active ingredients?

Seems that "Roundup CA" is the acetic acid version and "Roundup NL" is a
version using pelatgonic acid, are there any others?