In PEI there is fish kill from having fields too close to waterways. Not good, that.
Re. lawns and poisons, cosmetic herbicides, all lawns need biodiversity. Don't go complaining about earwigs if you reduce your lawn to grass only. Thus, dandelions can be used to make wine, low growing white clover to feed the nitrogen. Heck, just mow it, but don't think it has to be like your living room carpet.
Leave edges of lawns with some free growth. We need the little diverse critters who live in these spaces.
:C