For 10 years Ramon Arevalo, landscape superintendent for Long Beach, Calif., pondered the mystery of the Loynes Ave. traffic median. Someone was planting flowering cacti and long-tongued succulents on the once-desolate strip. But who?

It was, as Arevalo learned, Scott Bunnell, a reticent, 48-year-old mail carrier who for two decades has secretly dropped seeds and tended flora in 10 spots along intersections and rail lines in this community of 470,000; he goes anywhere funds and manpower are lacking. "I see this as my responsibility, to make my community better," says Bunnell, who revealed his identity to the Los Angeles Times. He's part of a "guerrilla gardening" movement that has sparked complaints in some communities where such activity violates local law. But in Long Beach, where gardening in public spaces is legal, his efforts make folks happy. Says Alan Bartels, who lives near Loynes Ave.: "I just thought the city was giving it some special love. I'm really impressed and grateful."

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