St. Gerlach is often show with a tree.

St. Gerlac was a 12th-century Dutch hermit. The Vita Beati Gerlaci Eremytae, written around 1227, describes his legend and life. He was a licentious soldier and brigand, until his wife died, at which point he became a pious Christian. He went on pilgrimage to Rome and Jerusalem. In Rome, he nursed the sick for seven years. He also performed rites of penance for the sins of his youth. When he returned to Holland, he lived as a hermit in a hollowed out oak. Legend states that when Gerlach had done enough penance, water from the local well transformed itself into wine three times as a sign that his sins had been forgiven.