No passport is required (yet) for entry into Canada. See http://travel.state.gov/travel/tips/...es_1229.html#c
where it says "CANADA – Passport or proof of U.S. citizenship such as a birth certificate, naturalization certificate, and photo ID required"

So he can go on Aug. 1 provided that he does have proof of US citizenship (presumably this is not an issue as it is also needed for the passport).