Photo: Diane Edwardson, July 14, 2015. Non-native, but scenic cactus is blooming at the Silver Lake Ave Public Staircase on the Red Car Property. (Click on photo to enlarge.)
Cactus and succulents are not only drought tolerant, they're fire resistant and once established, certain species (like those planted south of the Silver Lake Ave Public Staircase) make beautiful defensive landscaping that discourages criminal activity.