(photo by Bob: 2006-05-24 - explore)
Poplar Fluff
The poplar's reproduction strategy is to produce millions of tiny seeds and to distribute them widely on wind-borne pieces of fluff. Only a very small fraction find a suitable habitat of disturbed, sun-drenched ground. Most of the seeds are "wasted", coating the surfaces of local waterways, for example.
(There is a deer in this photo -- that barely discernible spot on the far shore just to the left of the near point. I didn't notice it until after putting the camera down.)