Poison yards? Keep children and pets of the grass for their own safety

Prof. Cricket and I walk at least two times a day. I had her pose by this sign. I suppose I should be careful, it says to keep pets and children off because the lawn has just been sprayed with a weedkiller.

Do you really want you yard to be poisonous to children and small furry animals?

What do you do to keep your yard free from weeds? Please post your comments.