|Is it safe to use grass clippings as a mulch for my vegetable garden or to make compost with if the grass has been treated with chemicals such as Chem-Lawn?|
|I wouldn't be comfortable using treated clippings. I'm not sure what types of chemicals they apply--but they may not be labeled as safe for food crops, and that could be where they end up. (Some chemicals take a very long time to break down.) Also, they may contain herbicides that could damage your plants--lawn "weed and feed" products can contain herbicides effective against broad-leaf weeds , but they don't affect grass so they're not a problem used on the lawn. Unfortunately, your vegetable garden is full of "broad-leaf" plants!
If this is from your lawn, have you considered switching to an organic type of lawn care company? Or perhaps even doing it yourself--there are lots of organic products for lawns now, and these would generally be safer to use in your gardens. "Organic" products tend to break down very quickly into harmless substances.