permaculture

[Bob <rmhoward@omninet.net.au>]

Toby Hemenway wrote:

 
> Otherwise there's a lot of farmers who couldn't
> undertake minimum tillage.

The "beauty" of Roundup is that it is absorbed primarily via leaves, and
almost not at all by roots; it also doesn't inhibit seed germination much.
Thus there can be plenty present in the soil when the next crop is planted,
with little effect on plant growth. So just because plants grow in a field
formerly sprayed with Roundup doesn't mean that the glyphosate has broken
down. Researchers found that in a field sprayed with Roundup and planted a
year later with lettuce, the lettuce contained significant amounts of
Roundup (don't make me dig up the paper to see what "significant" means!).
So if you use Roundup on food crops, you're eating it.
 

Whoa - this does not make sense - Roundup is specifically toxic to Shikimic
Acid pathways in plants - how can any plant especially one largely comprised
of leaves like lettuce have 'significant' quantities of glyphosate in it's
leaves and not be dead - unless of course you sprayed it on to kill it
- but this usually only happens with drug crops.

Soils with high organic matter and thus very active soil life will break
down toxins quickly, but I suspect that if you use Roundup, you won't have
good soil life for very long--it, and the surfactants it contains, are
toxic to soil life (less so, of course than, say, diazinon). And I assume
most people using Roundup are also using chemical fertilizers, thus they
probably don't have high organic matter.
>
> We should not jump to conclusions about the safety and hazard of Round up
> based upon reports from Columbia

The research I've seen, and that cited in the factsheet, all comes from
legitimate, peer-reviewed scientific journals such as Pharmacology and
Toxicology, Weed Science, Journal of Wildlife Management, etc. or from
documents that Monsanto presented to the Feds.

I'm not in favour of Round Up but several of the links posted have referred
to horror stories about animals dying, skin diseases etc. in Colombia.
Agent Orange was not the same formulation as 2,4 _ D or 2,4,5_T sold over
the counter in U.S.A. or Australia - for one thing it had about 100 times
more dioxin present. I don't know how toxic the surfactants used in Columbia.
Surfactants are detergents most are no more toxic than the stuff under
your average (non-green) kitchen sink. I wouldn't drink them either - but
the greatest environmental risk they pose is the phosphorus they contain
- not whether drinking surfactant is good for you. It's not. Big deal.

Round Up is deadly to frogs because of the surfactants in it.

The problem with surfactants is whether they break down. This has been known for a long time. Early household detergents manufactured in the 50's and 60's contained branched chain hydrocarbons which didn't break down -> lots of foam in the water. Later compounds don't have branched chains. But neutral anion detergents which are in common use today also present similar problems. It really does depend upon what the specific detergent (surfactant) being used is and what the data on biodegradability says and on what the by products are.

Soil bacteria and fungi will consume just about any source of carbon including intractable waste like dioxins given the right environment.

Minimum tillage is far better for Oz soils than previous methods of crop growing. Of course repeated application of glyphosate will affect the soil. If the same routine is applied again and again in the same paddock.  As far as the farmer is concerned what s/he is likely to notice is not reduced fertility but Roundup resistant weeds appearing. But this is an argument for crop rotation - and ultimately for leaving land fallow once every few years. Of course this goes against the profit motive and that's another story.

Weeds are just plants we haven't found a good use for. In the meantime whether I kill them with a rotary hoe or chemical spray like round up the real question to ask is not - how should I kill the weeds but how can i find a use for them. .
 

Regards Bob Howard
 
 
 

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