 Sometimes an honored birch tree would be named for a rusalka as part of Green Week.Some of the rites of Green Week (like making offerings of eggs and garlands) were thought to placate the rusalki so they would stay away from the village's agricultural fields for the season and thus not bring them harm.The rusalki are also associated with water and fertility, and so may be invoked during Green Week in an attempt to bring their moisture and vigor to the fields.