On 2/15/2020 4:39 PM, trader_4 wrote:
....

I've never fully understood the surfactant thing. If you read the directions
for the glyphosate products, they say to use a non-ionic surfactant.
But what is dishwashing liquid? From what I could gather, it was impossible
to tell, even for specific brands. What difference does non-ionic vs
non make? IDK. And you'd think in the typical 2.5 gal and smaller jugs
which individuals, small biz, etc would use they would just mix the
surfactant in. Razor does, I think RU does too. But there are lots of
other products that start talking about the damn surfactant instead of just
putting it in. I can understand not putting it in for large quantities,
like a farm would use, so they can use the one of their choice.

"There are different types of surfactants. Each herbicide product has
specific adjuvant requirements that are specified on the product label.
The label will provide guidance and adjuvant options; to address tank
mixtures, environmental conditions, or weed species characteristics."

"Some herbicide products such as Roundup PowerMAX® II Herbicide, are
formulated with sufficient adjuvants in the herbicide formulation and
may not need additional adjuvants added to the spray mixture in all
cases. Some products have specific recommendations for spray adjuvants
that the user must add to the spray mixture. The user should pay
particular attention to label instructions for each tank mix product
because label recommendations may differ for each product."

"Each herbicide manufacturer may have supplemental labels or fact sheets
that provide additional guidance for the use of adjuvants for specific
application situations, weed species, crops, or tank mixtures. There is
a diverse array of adjuvant products and brands. The user must
understand the composition and function of each product to properly
match the adjuvant to individual herbicides or each product in a tank
mixture and application conditions. Comprehensive information on
commercially available adjuvants can be found at
http://www.herbicide-adjuvants.com"

Basically, what surfactant to use depends on the chemical
characteristics of the herbicide such that the two are compatible and so
have the desired net effect. It's all just chemistry (physical
chemistry, actually).

The fundamental difference between a detergent and soap is the inclusion
of surfactants. They have the intent and effect of being able to break
the surface tension between water and otherwise mostly water-insoluble
substances like grease. Same idea with the surfactant on herbicides.
Virtually any detergent uses a combination of ionic and nonionic
surfactants to interact with the targets its intended to get to. Hence
their reasonable effectiveness as herbicide surfactants for at least
home use, but for larger applications they're not nearly as effective as
products designed for purpose and actually comparatively much more
expensive in those volumes.

Here's link to a really nice presentation, actually I just saw after
clipping all the above...

https://conference.ifas.ufl.edu/aw15/documents/Presentations/2%20Wed%205A%20850%20Jay%20Ferrel.pdf

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