As the above thistle weed had become very prolific in my bushes and budding plants I went in search of some way to kills them that wasn't going to cost me a fortune or harm the environment and my search turned up an article by Don Comis at The USDA's Agricultural website about spraying a vinegar solution on the leaves to kill them.
It cited that researchers used at 5% to 20% solution to kills the weeds and that most household vinegar is a 5% solution.
I didn't want to risk damaging the bushes or any of my budding plants, so I watered my solution down to:
1 cup of vinegar
1 cup of water
and put the solution in a spray bottle and sprayed it on some of the leaves.
It worked! This is what the sprayed leaves looked like the next day. The weed was dying and there was no harmful effect on the bushes or plants. I will probably just use the vinegar full strength in a bottle next time to finish off the weeds.