I'd love to let them play (supervised of course!) in the back yard for a little bit, but am concerned because I sprayed Weed B Gone 2 weeks ago. Should I wait until after the first mowing to make sure there's no residue? The package says it's dog safe after it dries, but I know the chicks will be pecking and eating out there. Will it even be safe AFTER the first mowing? I just moved in the end of summer and have been doing a lot of work out here and the weed spray was just part of what needed doing. Normally I'm organic.