Interesting ...

[Neil Jones]

On Tuesday 16 April 2002 05:55 pm, Hank Brodkin wrote:
> Joel -
> The chemical referred to is atrazine.  Is this sold under the brand name
> "Roundup"?
> A lot of  Roundup is used out our way to control desert broom (bacharis
> sarathroides), an native shrub that colonizes disturbed soils.  Since we
> live next to a wash we have a lot of it.  It is an excellent nectar plant
> for butterflies, native bees and other insects, so we like it - and we
> don't use poison on our property - but almost everybody else does.
> We also have had frogs in our small pond for about a year but have yet to
> see egg masses.  I know the previous property owner used Roundup - he left
> some in the garage, but this was pre- 1998.
> Hopefully atrazine is not Roundup!


The active ingredient  in Roundup is Glyphosate or chemically 
N-Phosphonomethyglycine.
Glyphonsate works by disrupting the activity of an enzyme called
5-enolpyruvylshikimate-3-phosphate synthase. The enzyme catalyses
an important stage in the synthesis of aromatic amino acids.
Essentially Glyphosate blocks protein synthesis.

Since this particular pathway does not occur in animals it cannot affect them.
However there are a number of other chemicals in Roundup, surfactants etc.
It is therefore quite possible it would affect frogs.

Glyphosate must have an effect on the soil, despite marketing claims to the 
contrary, since many microorganisms _do_ use the enzyme it disrupts.
Detecting the changes may however be difficult.

Anyway as you have pointed out Hank, using it isn't good for butterflies.


--
Neil Jones- Neil at nwjones.demon.co.uk http://www.butterflyguy.com/
NOTE NEW WEB ADDRESS
"At some point I had to stand up and be counted. Who speaks for the
butterflies?" Andrew Lees - The quotation on his memorial at Crymlyn Bog
National Nature Reserve

 
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