The bitterweed (Hymenoxys odorata) plant is a member of the sunflower family. The mature plant can be toxic to livestock, especially sheep. This beautiful specimen was observed along the edge of U.S. Highway 64/412 southeast of Garber OK.
I'm not certain, but I think this photograph may actually depict Helenium amarum. They look very similar, but Hymenoxys odorata can't compete well with grasses and therefore usually grows isolated from them. Helenium amarum (bitter sneezeweed), on the other hand, readily competes with grasses, much like the plant in your photograph. It isn't nearly as toxic as Hymenoxys odorata, but it gives milk a bitter taste if it is eaten by dairy cows. Regardless of which species it is, though, this is a beautiful photograph! --KJ