The Liberty Tree (1646-1775) was a famous elm tree that stood in Boston, near Boston Common, in the days before the American Revolution. The tree was a rallying point for the growing resistance to the rule of England over the American colonies. In the years that followed, almost every American town had its own Liberty Tree -- a living symbol of popular support for individual liberty and resistance to tyranny. In some locales, a Liberty Pole rather than a tree served the same political purpose.
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Aside from the concrete tree, the term "Tree of Liberty" is associated with Thomas Jefferson's quotation, "The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants".