These are names of "Neighborhoods" within the city limits of their larger urban cities.
Smoke Tree is a area or neighborhood within the larger city of Palm Springs, in the County of Riverside, CA. I believe the Desert Regional Medical Center is located in this Smoke Tree neighborhood and if your aunt was vacationing, traveling thru, or had a second home and suffered a medical condition resulting in her death in this Medical center then that is why it is listed as place of death.
Barona Rancheria is a neighborhood within the City of Palm Springs.
Magnoilia Center is 1 of 26 neighborhoods within the larger City of Riverside, in the County of Riverside, CA. You can see a map of where it is on the City of Riverside's website-Planning Department.
According to the Riverside Press Telegram Website of their circulation there are 14,941 households within the Magnolia Center neighborhood and 11,029 households in the Smoke Tree neighborhood.