On Sun, 3 Aug 2003 23:15:36 +0100, Martin Brown wrote:

There is one slight catch though. The overall environmental impact of
making all that black plastic sheet is greater than that of the tiny
amount of glyphosate needed to achieve the same effect.

I am quite prepared to believe this. A professor of applied
chemistry at our local university once worked out the total
inputs of non-renewable and renewable resources into the
manufacture of the hated styrofoam coffee cups and the more
favored paper cups, respectively. He concluded that stryofoam
cups, overall, use fewer/less non-renewable resources than do
paper cups, contrary to popular belief.


--
Rodger Whitlock
Victoria, British Columbia, Canada