Hawkweed oxtongue (Picris hieracioides) is described in my field guide as our most hawkweed-like non-hawkweed! Well, that is a great help on two counts; what does a hawkweed-like hawkweed look like and how do you tell this hawkweed look-a-like from true hawkweeds?
Although nothing like a dandelion I describe these hawkweeds and their relatives as being dandelion-like. By that I mean flower heads made up of a cluster of narrow yellow petals coming from a single seed box at the top of the stem. It is there the similarity stops but it is amazing how many people think these hawkweeds and the like are actually dandelions!
Hawkweeds, Hawkbits and hawkbeards account for about fifteen similar species of flowers we see in Dorset and the differences are, at first, hard to take on board but with practice it gets easier! Hawkweed oxtongue is a tall plant, it has a red stem which branches and branches again (just like a tree) and on each branch is one yellow (as opposed to golden) flower head. It is found in grassy places usually on lime so look for it on Portland and along the Purbeck coast.
There are other differences to the various similar species but the ones I have listed will get you started.Hawkweed Oxtongue: a hawkweed-like non-hawkweed