Anne Saxelby might be the foremost proselytizer for local cheese, but she does more than sell the stuff at her Essex Street Market stall. She organizes field trips called Day A-Whey, and the first of the season is scheduled for this Sunday. A chartered coach departs from the market at 8:30 a.m., destined for Wölffer Estate Vineyard in Sagaponack for a vineyard tour and alfresco picnic lunch. Next, to Bridgehampton for a tour of Mecox Bay Dairy, whose owners switched from growing potatoes to making Jersey-cow’s-milk cheese only a decade ago. (For those curious about that hot-button beverage, raw milk, here’s your chance to sample it.) If the weather’s fine, there’ll be a stop at a local beach before the drive back (and before the summer crowds swarm in). Tickets cost $95; they're available at saxelbycheese.com.