Posted at http://www.passportcanada.gc.ca
As of January 31, 2008, if you travel to the United States by land or water, a United States law will require you to present:
*** a government-issued photo ID, such as a driver's licence, PLUS a birth certificate or a citizenship card;
OR
*** a valid passport
OR
***for those 18 and under, a birth certificate
Canadian citizens flying to or through the US must present a valid Canadian passport.
