Heads of little yellow flowers decorate the dunes. This is sand verbena, or Abronia latifolia. Its prostrate stems are sprawled like sunbathers across the sand, raising their leaves and blossoms like a lazy wave. The flowers are some of the showier native dune blooms, and have a lemon-verbena scent. The succulent, scalloped leaves are pretty in their own right–especially when lightly dusted with sand.
You can find this little flower on the dunes and strand, and in coastal scrub, from Santa Barbara to Washington State. Its long, stout roots are edible and somewhat sweet. They were usually harvested in the fall by coastal tribes.
I saw spotted this verbena on the white sands of Asilomar during EcoFarm–a great conference, and a lovely state park and beach to visit at any time! 
Flowers Of Marin 