"PA" wrote in message
...
thanks every one for your input, I'm still in two minds though....
the bit I don't get is: if no residue is left in the soil, what about when
the roots of the weeds start to break down wont they release chemicals,
which will be then taken up by whats ever growing?

When the roots rot, the residue enters the soil where it is neutralised like
the original stuff was when it fell on the ground.

[Franz Heymann]

the trouble is I've got about 450 square meters to clear and its taken
about
an hour to do one properly
and now I'm dreaming of roots
thanks
Paul