Is there anything for rape,brassicas,chicory,vetch,turnips,etc that can be used to kill weeds.I am having a problem with ragweed.

How big is your plot, if not too big it might pay you to walk thru it and pull them out by hand, or you can make a roundup wick and just rub it across the unwanted plant,farmers used to use wicks for the middles of vegetable rows to rid the weeds.

Ask the guys at the Whitetail Institute. I used their Arrest herbicide for grass this year and it did real good. They have a herbicide for weeds, it may help you out. I haven't tried it yet but plan to.