PASO ROBLES, Calif. -- Wild spring weather across California's wine country has been enough to drive a vintner to drink. From killer snow in the Sierra Nevada foothills to dry-season downpours along the coast to a hard freeze in temperate Paso Robles, 2011 is proving to be a challenging vintage. "That's what makes this business so damned interesting," said Jim Fiolek, executive director of the Santa Barbara County Vintners' Association. It also can keep winemakers up at night. Jason Haas, general manager of Tablas Creek Vineyard near Paso Robles, said winemaker Neil Collins has experienced many sleepless nights this spring.