Why are willow trees leaves so long and floppy?

Have you ever seen a willow tree? They sometimes have long branches that hang down to the ground and make them look like green, leafy waterfalls.  But why do they have this unusual shape?  We asked botanist Brandi Cannon-Force  to help us find the answer.

Got a question that you just can’t find the answer to?  Don’t weep! Send it to us at BrainsOn.org/contact, and we’ll root around for the answer.