where is colusa county in ca?
Colusa, CA. Online Offers. Colusa (formerly, Colusi, Colusi's, Koru, and Salmon Bend) is the county seat of Colusa County, California. The population was 5,971 at the 2010 census, up from 5,402 at the 2000 census. According to the United States Census Bureau, the city has a total area of 1.8 square miles (4.8 kmÂ²), all of it land.