TOM DAVIES was driving last fall down Highway 29, the two-lane blacktop that serves as the Napa Valley’s main drag, when he saw something that literally stopped him in his tracks. “There was a sign on the side of the road that said, ‘Cabernet Grapes for Sale,’ ” he recalled, still incredulous that economic desperation had forced a Napa grower to hawk the region’s hallowed fruit like a load of zucchini.

In the 30 years that Mr. Davies, the president of V. Sattui Winery and Vineyards, has worked in the Napa wine business, he has never seen a sight quite so unsettling. “Grapes were left hanging on the vine last year,” he said.

This unusual predicament is not easily remedied at a time when vintners are awash in wine. Read more...