Mike - No, It's not fennel, it's Queen Ann's Lace or sometimes called Wild Carrot or Ammi Majus. It is considered a weed here but is actually a herb and the first year tuberous root is edible. When crushed it gives off the scent of carrot.
Here are some references: http://www.flowerpossibilities.com/encyclopedia/22.htmlhttp://rosesfromatoz.com/rosesaz_queen.htmlhttp://www.bio.brandeis.edu/fieldbio/Wildflowers_Site/QueenAnnesLacePage/QueenAnnesLacepage.html
The origin of the name is reputed to be based upon an English legend. Supposedly, when the future Queen Anne arrived from Denmark to became the queen of King James I of England, wild carrot was still a novelty in the royal gardens. The legend states that Queen Anne challenged the ladies in waiting to a contest to see who could produce a pattern of lace as fine and lovely as the flower of the wild carrot. The ladies knew that no one could rival the queen's handiwork so it became a triumph for Anne. She however, pricked her finger with a needle and a single drop of blood fell into the lace, that is said to be the dark purple floret in the center of the flower.
Queen Anne, Queen Anne, has washed her lace
(She chose a summer's day)
And hung it in a grassy place
To whiten, if it may.
Queen Anne, Queen Anne, has left it there,
And slept the dewy night;
Then waked, to find the sunshine fair,
And all the meadows white.
Queen Anne, Queen Anne, is dead and gone
(She died a summer's day),
But left her lace to whiten in
Each weed-entangled way!
By Mary Leslie Newton.