When the Lewis & Clark Expedition camped in October 1805 where Lewiston is now located, they recorded in their journal that the area consisted of "open plains, no timber of any kind, a few hackberry bushes and willows excepted." In the late 19th century, the merchants of Lewiston realized that they needed to plant trees to counter the summer heat. Poplar trees were planted along Main Street and the "poplars of Lewiston" were famous for years.
Tree planting continued to be practiced throughout the 20th century, and Lewiston is now home to more than a dozen examples that are Idaho Champion Big Trees in their species.