A serious viticultural concern for Chablis vineyard owners is frost protection. During the bud break period of a grapevine's annual cycle, the Chablis region is vulnerable to springtime frost, from March to early May, which can compromise the crop yield. Formerly, the financial risk involved saw many producers turn to polyculture agriculture, pulling up vineyards to plant alternative crops. The 1957 vintage was hit particularly hard by frost damage: the regional authorities reported that only 11 cases (132 bottles) of wine were produced.