There are a number of designated Witness Trees in the United States. The National Parks Service defines these as "silent sentinels of storied landscapes that help connect people, history, and places." In 2006 the NPS developed the Witness Tree Protection Program which led to the identification of 24 historically significant trees in the D.C. area including the magnolia trees Andrew Jackson planted for his wife, an elm on the mall in that is meant to commemorate all of the elms that died of disease in the 1950's, and a circle of trees near the Vietnam War Memorial that were there to "witness" the building of the memorial. There are also trees isolated for having been present for many of the major wars that helped shape the Unites States into what it is today. Trees at battlefields of the Revolutionary and Civil Wars as well as trees that saw the War of 1812 have been designated as Witness Trees by the NPS. Additionally, individual artists and communities have made efforts to acknowledge trees that had been present for some of the darker moments in the nation's past. There are trees along the Underground Railroad and trees at the sites of the WWII Japanese internment camps that have been acknowledged by the surrounding communities as having witnessed pivotal moments in history.

On average, 125 people die from gun-related deaths every day. For these Witness Trees I travel to some of the sites where the violence took place, identify the trees that were witness and make a formal document of each tree.