[Terrapreta] DOes charcoal absorb Glyphosphate?

[Kurt Treutlein]

Sean K. Barry wrote:
>  Hi Max,
>
>  You say: However, charcoal is ineffective against metals, Na, K,
>  alcohols, *glycols*, acids, and alkalis." Its use is also widespread
>  amongst animal farmers. There has of recent been discussion and
>  concern on this list about whether Roundup (Glyphosphate) will be
>  absorbed by charcoal and still remain effective.  I do not know the
>  chemistry of this, but is it possible that your statement above
>  relating to glycols may be an answer that NO Glyphosphate will not be
>  absorbed by charcoal?   I don't know who could answer this really.
>  Maybe is just needs to be tested.  Should I pour some roundup onto
>  soil containing charcoal and see if it will never grow anything ever
>  again?  If you pour Roundup on bare soil it won't stop weed seeds
>  from growing.  It has to be poured on the plant leaves themselves and
>  it "wears out" its effectiveness over time.
>

Roundup is de-activated by contact with soil. This is supposedly it's 
great advantage, overspray onto soil won't affect anything. It is only 
when it is sprayed onto actively growing plants that it is translocated 
through the plant down to the roots, which causes the plant to die. If 
you mix Roundup with muddy water, the resultant mixture generally won't 
work. Apparently the Roundup interacts with clay platelets in some way 
and stops working. Monsanto claims that it won't accumulate in the soil, 
but I used it while growing green beans, as a pre-emergent spray and I 
noticed that after some years use it seemed to affect grasses and weeds 
that came up after I stopped using it.
Applying the concentrate directly to the soil is a whole nuther thing, 
but who would do that. The stuff costs about $20/liter.
As for "wearing out", it only works when sprayed onto a plant. Once the 
plant dies, there is no remnant effect, except possibly as I mentioned 
above. Some other weedkillers do in fact remain in the soil and continue 
to kill. Nasty things those.

Kurt