Arbor Day is observed in Guam on the second Tuesday in October, aligning with the end of the rainy season to facilitate tree planting. This celebration mirrors the American tradition, originating from the first Arbor Day celebrated in Nebraska on April 10, 1872, which became an official holiday by 1885 and spread to various U.S. territories, including Guam. The day is primarily recognized by the Department of Agriculture’s Forestry and Soil Resources Division along with forest activists, although it does not attract widespread participation from the general public. On Arbor Day, the Department of Agriculture replaces sick trees, and volunteers, including students, may assist in these efforts. The focus is on ecological observance and promoting the health of Guam’s forests.