The story behind these street signs

The Times' Lynell George explore the street art that has become something of a rage along the streets of Los Angeles. They have a message, George found:

IT COULD very well be a mirage: A trick of the glaring morning sun or something misread in the pre-caffeinated early morning haze. But no. Upon closer inspection, that brown-and-white sign, hanging just beneath the red slash of the "No Left/U-Turn" symbol on a sparsely landscaped traffic island, proclaims exactly what you first thought: "The Islands of LA Nat'l Park." The territory it demarcates along a busy stretch of Glendale Boulevard as it eases into Echo Park seems, at first, unremarkable: some California native brush; flattened and faded Diet Coke cans; Energizer batteries. Nearby, vibrant goldenrod poppies push up from the dirt. And sure, depending on the time of day, you'll find a few regular "campers" -- a couple of reliably resolute panhandlers: one with a dog, another alone and with his own sign whose message has become garbled, streaked and bloated from rain.