Involucral bracts spine-tipped, leaves pinnatifid. Leaf bases not decurrent.
This may be bull thistle (Cirsium vulgare), but seems more like the native pasture thistle to me.
From glorious to bird seed! I believe it to be a field thistle based on the shape of the flower head and length of the petals.
Field thistle blooms around summer and fall can be either pink or purple in color. It can grow up to 6 feet in height. The Field thistle can be found on eastern United States. This particular thistle was found on the edge of a pine forest.