Green. no one here remembers when it started. maybe three days ago, after seven months of brown. s "It comes on like blindness," one of the cowboys says. "One day the green puts your eyes out, and you didn't even see it coming." s I'm standing on the mountainous top of Santa Rosa island off the Santa Barbara coast. Out across the channel waters - white-capped, big-swelled, and shark-glutted - I can see, on the California mainland, the ridge where my house is perched. From there, the view down a canyon perfectly frames Santa Rosa. It is as if this marine shard were the missing half of the land where I live, the other side of my green mind. s Santa Rosa island is shaped like a four-pointed star plucked in the middle and dropped. The east and west arms reach for the shore of the next islands in the chain. They were once linked together in a 60-mile-long island; now the passages between them are cross-currented, choppy, wild, and dangerous, churning gyres rotating counterclockwise, mixing warm water into the cold and bathing the islands in clear seas. s At 53,000 acres, Santa Rosa is the second largest of the eight Channel Islands and has been run as a cattle ranch for almost a hundred years by the Vail and Vickers families. s Plunging down a rough dirt track in the Vails' battered pickup truck, we go east toward Bechers Bay, the steep land splaying out into broad coastal grasslands. Two foxes, endemic to the island, pounce on a field mouse, oblivious to our passing, reminding me that the four northern islands - Anacapa, Santa Cruz, Santa Rosa, and San Miguel - are sometimes called the Gal¿pagos of the Northern Hemisphere.