Songo'o broke a 1-1 tie on a low shot that Whitecaps goalkeeper Joe Cannon couldn't stop despite getting a piece of it.
Darlington Nagbe also scored for the Timbers (6-13-6), who notched their first win since July 3.
Kenny Miller notched his first MLS goal just before halftime for Vancouver (10-10-7), which lost its third straight.
Sign language interpreter at Mandela service called out as fake on Twitter
Police: Sword-wielding man demanded free tacos