What is the scientific name for this?

Question

http://farm4.static.flickr.com/3249/2794569137_e1a3536e89.jpg

Answer 1

It is a foxtail grass, but it's one from the genus Setaria, not Alopecurus.  Yours looks like Setaria viridis (green foxtail):  http://www.ppws.vt.edu/scott/weed_id/set...

Added:  I took another look at your photo (hard to tell the scale) but if the seed head curves as it seems to be trying to do, it could be Setaria faberi:  http://www.ppws.vt.edu/scott/weed_id/set...

Answer 2

A weed,

Answer 3

It is one of these Foxtail grasses:

http://en.wikipedia.org/wiki/Alopecurus