Is there a safe pesticide to use around chickens?

Thanks, all, for the comments, the follows to @urbanchickens and the emails. I'm now getting enough email sent directly to me that I can sustain a weekly Mailbag feature. So, without further ado:

A dear reader, Lo, recently sent me the following email request:

I am going to be doing some yard work for a friend who keeps several chickens in her urban back yard. Obviously I cannot use any pesticides in her yard and garden because of the birds, is there any alternative to help control weeds and kill invasive non-indigenous plants?

Right away, I knew I was in over my head, so I referred her to the kind folks over at Seattle Tilth for help. Here's what Laura of the Garden Hotline had to say:

There is no alternative pesticide to spray on weeds that is safe for chickens. The only effective herbicide that is "natural" is made of acetic acid and this still would be questionable to use around the birds. The good news is that chickens eat weeds! They could make short work of annual weeds and grasses and even dandelions. The scratching that they do can disturb weed growth as well. They can wreck other desirable plants as well so the use of chickens must be done with caution! Noxious weeds and more persistent perennial weeds like dock will need to be hand removed. You could also try flame or heat weeding though this requires special equipment and propane tanks. Hot water can kill annual weeds pretty effectively straight from the teapot! Otherwise it is a matter of hand pulling and then mulching areas you do not want growth of weeds. Getting to weeds before they go to seed is crucial to interrupt their life cycle.

Thanks, Lo, for the question as well as for sharing Laura's response.

Is there something about urban chickens you've been trying to get an answer to? drop me a note or leave a comment and we'll learn together!