
As JG says, Roundup is fine around Pets.
I use the industrial stuff that I am licenced to use and use the mix 10-20 times stronger than the 'layman' can buy(I AM allowed to LOL) , and what I do just to on the safe side, is make sure you keep your dogs in for an hour after spraying. Or put it on just before you go out, or to bed :) :)
The best thing to do is to stand on the docks, not to break them but to break the surface of the leaves before spraying, as this will help the chemical (Glysophate in Roundup) get into the system.
HTH
Lea :) :)