I called AAA, as well as looked online at multiple sites, and it changed in June. You need these documents.
Land and sea travelers are encouraged to have a valid U.S. passport. If they do not have a passport, they should be prepared to provide a government-issued photo ID (e.g. Driver's License) and proof of U.S. citizenship such as a U.S. birth or naturalization certificate.
When entering Canada from the United States, U.S. citizens must show either a U.S. passport or other proof of U.S. citizenship - such as an original or certified birth certificate together with photo identification. U.S. citizens entering Canada from a third country must have a valid passport. A visa is not required for U.S. citizens for a stay up to 180 days.