One or a few strains per region isn't exactly what I'd call a healthy amount of biodiversity.

I don't know much about the Dicamba topic, but it looks like a nasty herbicide and Monsanto is producing GM seeds that are resistant to that, probably to overcome the natural resistance to glyphosate that pigweed developed. It seems like there is a lot of controversy around it. Care to comment more on that topic? I think there are some interested readers that you won't bore.