On Wed, 11 Jan 2012 00:49:13 +0000, Janet Tweedy wrote:

So what would you use to kill moss on a tarmac driveway then jake?

Moss doesn't like copper. A known method to keep moss at bay of roofs
is to attach a heavy copper wire along the ridge line. Enough copper
is erroded by rain to stop moss growing.

You'll still have to mechanically remove what is already there but a
regular wash down with a copper salt solution should stop it
returning. I'll leave it to the reader to find out which copper salt
is the most effective. B-)

--
Cheers
Dave.