"Kay" wrote in message
...
In article , Franz Heymann
writes

"Des Higgins" wrote in message
...

[snip]

Bad means making a mess of other species which are native or
poisoning the
kids.

That is an untenable generalisation. South Africa imported, from
Australia, the insect Cactoblastus cactorum in order to destroy
large
areas of prickly pear in the Little Karoo, thereby making hundreds
of
thousands of acres available for grazing land.


So what are you saying here, Franz - I don't quite understand your
gist.
SA imported and alien to destroy another alien to create grazing
land,
which may or may not be the natural vegetation for the area .

I was under the impression that the prickly pears were indigenous.
Perhaps I am wrong about that.
If so, my point becomes rather weak.
On your final point: I have no objection to humans cultivating useful
plants, indigenous or otherwise.

Franz