Even while fading and going to seed, the Bur Marigolds Bidens cernua nod as their seed load gets heavier. They are called 'Nodding Bur Marigold' for good reason. That makes them sound benign but their middle name 'bur' refers to the hard angled seeds with 4 barbed hooks that give them a free ride on passing animals or people to where they might sprout anew.
