Do USA Green Card holders need a Visa to return back to the USA from Canada?
Not only can you make this trip without a visa; you don't even need a passport.
Here you can see that Canada admits US permanent residents with only their green card:
When travelling by land or sea directly from the U.S., you will only need to provide proof of your U.S. lawful permanent resident status (such as your Green Card).
Here you can see that the US admits its permanent residents with just the green card:
What documents do I need to present to reenter the United States?
If seeking to enter the United States after temporary travel abroad, you will need to present a valid, unexpired “green card” (Form I-551, Permanent Resident Card). When arriving at a port of entry, a U.S. Customs and Border Protection Officer will review your permanent resident card and any other identity documents you present, such as a passport, foreign national I.D. card or U.S. Driver’s License, and determine if you can enter the United States.
It's not extremely obvious from the quotation above, but "any other identity documents you present" implies that you aren't required to present these other documents. If you do present them, the border officer will examine them, but if you don't, your green card should suffice.
Keep the following in mind, however:
- The above answer applies only to surface travel. If you fly, you need a passport.
- The above answer assumes that you have been away from the US for less than one year. If you've been away for longer, you risk being seen as having abandoned your permanent resident status, and one way of dealing with that is to get a "returning resident visa." Furthermore, absences of six months or more can delay your eligibility for naturalization. The international travel page has a brief discussion of these issues, including relevant links.
And some random text to make the minimum limit that I didn't previously know existed.