This is the first time I can remember ever seeing this plant. I always thought Bachelor's button had purple flowers. This was the ONLY specimen like this we saw in our 5 mile hike.
Yes, it's bachelor's buttons, Centaurea cyanus - it's naturalized from garden plantings, if you are seeing it in an otherwise wild area. The flowers range from blue to white to pink to purple. Edit to correct spelling of species name.
I did not know it was invasive, but at least it was not horribly invasive. As I mentioned it is the only one we saw the entire hike. Thanks!