I am not sure that is necessarily the best place to discuss weeds. When everyone settled on "pests", we were trying to convey "destructive insects and critters". Here's the thread:
The thread "Insects and Disease" in
Site Talk forum
I thought KAMasud made a great point, too, about the difficulty of defining what a "weed" really is. I see dandelion for sale (for culinary and medicinal usage) all of the time but I also understand it is a pain to many gardeners.
