Many California growers can’t find buyers as the industry produces more wine grapes than the market wants. Wine consumption is declining globally as people drink less.

It’s harvest time in California wine country, but many growers are struggling to sell their grapes as changing drinking habits have caused demand to plunge. The decline is forcing some growers to tear out vineyards that their families have grown for generations.

Wine sales have decreased by more than 20% over a five-year period, causing prices paid for grapes to drop and prompting California growers to take roughly a quarter of the state’s vineyards out of production. Many growers are having to decide whether to harvest at a loss, leave grapes on the vine or replace vineyards with crops more in demand such as almonds, walnuts, pistachios and olives.

Third-generation grower Bill Berryhill said it means another year of losing money and wasting hundreds of tons of healthy grapes.