Yes, you can throw it on the sand (or dirt). (Make sure it is 'construction', or 'mason' sand. Made of up particles of various sizes, vs play sand which is all the same size, and not what you want).
I keep a large cement mixing tub with dirt/ash/peat moss in my run, too, and they like picking at it.
Edited by lynnehd - 4/24/16 at 9:39pm