Dandelion greens are great (make sure they haven't been exposed to chemicals); I know that clover greens are okay for vegetarian lizards like Uromastyx, but I'm not 100% sure about turtles. I'm sure they're fine, but we'd might as well wait for somebody who's actually tried it.
Some musks (and muds) will eat vegetables or aquatic plants; however, they don't really need it. They're predominantly carnivorous animals. As for the RES--as funny as it sounds, I just took pieces of lettuce and poked them in the face with it until they got angry enough to bite it. The rest is history! Also, please be sure to rinse off any greens thoroughly before offering them to the turtle(s). They often carry parasite eggs.
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