Mike wrote:

Okay,

I've got a concrete drive which gets marked badly at this time of year by
starlings who are eating berries and/or blackcurrants and leaving purple
marks everywhere.

I have tried scrubbing the concrete which brings up the original colour of
the concrete but the bird mess mark remains.

Any advice on what household cleaner or chemical would help remove these
stains ?

Thanks.

Mike.
Coca-cola (or pepsi) - I've used it to remove oil stains from concrete
so I'd expect it to work on most things.

Clean the worst of the mess off with a hose or brush, then apply the
cola. Keep the area well wetted with cola and work backwards and
forwards over the area with a stiff brush. When finished, rinse of well
with a hose.

Also works well in cleaning up corroded metal - and rots teeth!

--
Larry Stoter