On Mon, 28 Jun 2010 13:33:57 -0400, Jim Elbrecht wrote:
[maybe not-- if my math is right, 250 gallons spread over 400 square
feet would be about 1" deep.. . . can that be right?]

The coverage part of your math is OK, but I suspect you miscalculated the
area of your lawn. 400 sq ft is a decent sized living room, less than 1/100
of an acre.

Edward