I think the plant that is centered in both pictures is curly dock. Either that or sorrel. The plant with the yellow flower in the second picture is bitter sneezeweed The solution for all those is the same in pastures: Product like Grazon Next HL, or Weedmaster (2,4-D + dicamba) are the best choices. No grazing restriction with either of those products.

If you need more assistance contact your local Clemson Extension Office. http://www.clemson.edu/extension/co/index.html