To prepare for Dyngus Day, Eddy Dobosiewicz drives to an abandoned lot in east Buffalo, N.Y., in search of an elusive commodity: pussy willows.

Dyngus Day celebrations, to be staged Monday in Buffalo and a handful of other U.S. cities, trace their roots to ancient Polish fertility rites centered around the end of Lent and the advent of spring. As part of the festivities, young men traditionally splash water on women they fancy. Women carry pussy willow branches to hit the men they like.

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