Dandelion

I found only one plant of this daisy-like flower on the block ... nearly pulled it out when I was attacking St Johns Wort because it was a yellow flower.

I left it because I don't know if it is native or a weed. I was somewhat surprised to see it set seed like this ... must be some sort of dandelion.  There is a native dandelion but is that one or them I wonder?

There is a clump of giant dandelions down near the back fence.